TOTO S550e Washlet vs Bio Bidet Discovery DLS: Bidet Toilet Seat Comparison


The TOTO S550e Washlet and the Bio Bidet Discovery DLS are two of the top high-end luxury bidet seats on the market today. The TOTO S550e is widely considered the highest quality bidet seat that money can buy.  The Bio Bidet DLS is the new challenger in town and is ready to leave a lasting impression. If you’re in the market for an ultra high end bidet seat to complete your bathroom, these two are sure to be contenders.  Let’s put them side by side and compare the TOTO S550e and Bio Bidet DLS to see which bidet seat is the best for you.


TOTO’s high end washlets are known for their low profile design and luxury appeal. The S550e has one of the lowest profile silhouettes of any fully featured bidet seat. At just 4 ¾” tall in the rear, its design is modern with a unibody lid that covers the entire rear panel when closed. 

The TOTO S550e comes in two different lid styles: contemporary and classic. The classic lid has a decorative beveled edge that’s suited for more traditional decor, while the contemporary lid will be more minimalistic.

The Bio Bidet Discovery DLS also has a sleek, low profile design. Standing at 4.6” in the rear, the DLS is slightly lower in profile than the TOTO.  Its silhouette is comparably sleek and modern and represents a big improvement over past Bio Bidet models.  It carries a nice luxury appeal like the TOTO, with the only major difference in design being the exposed rear panel across the top.  

All in all, both models represent the latest in modern bidet seat design.  

Measurement Bio Bidet DLS Discovery TOTO S550e
Front Height 1 3/8 in 1 7/16 in
Rear Height 4 2/3 in 4 3/4 in
Length 20 7/8 in 20 7/8 in
Width 15 1/16 in 15 1/16 in
Electrical Cord 48 in 48 in


Spray Capability 

The Bio Bidet DLS has above average spray pressure compared to the market.  It delivers a robust spray that is capable of effective cleansing. The DLS oscillates its nozzle in the rear wash function by default, a nice shortcut feature for users that prefer it.  

The TOTO S550e also offers a nice strong spray that is nicely refined. The S550e has two different spray patterns: a “soft spray” and a “hard spray.” The default “soft spray”  setting is a wider, softer spray pattern that soothes as it cleanses, while the “hard spray” is stronger and narrower and feels more like other bidet seat sprays on the market.

The TOTO’s hard spray option and the Bio Bidet’s rear spray feel very similar and are of similar strength when set to max.

Water Heating Type

Both the DLS and the S550e utilize tankless water heating technology. Both of these top of the line bidet seats offer endless warm water with very  minimal lag time in the beginning of the wash. In our testing here at BidetKing, both models showed consistent temperatures throughout the wash cycle and temperature changes were fairly rapid. 

Automatic Seat and Lid

Another notable feature these two models share is their automatic seats and lids.  Both units have proximity sensors and can be set to raise when a user approaches and close when the user leaves.  There are also manual buttons to control the seat and lid if the auto feature is disabled.  Both the Bio Bidet and TOTO feature smooth motorized actions and neither model slams the lid against the toilet tank.  Due to the motorized design, neither lid is sittable.

Unique Features

Bio Bidet DLS Discovery:

UV Nozzle Sterilization- The Bio Bidet DLS sports a UV nozzle sterilization system which helps eliminate bacteria and other virals. A very high tech and truly rare feature not found on many bidet seats.

5 Year Warranty- Bio Bidet spared no expense when it came to their high line bidet, offering a 5 year full manufacturers warranty. This warranty covers 100% of parts and labor for the Bio Bidet DLS so that you don’t have to worry about a thing. It’s very generous, especially when compared to TOTO’s standard 1 year warranty.  

TOTO S550e: 

EWATER+ - EWATER+ is a very unique feature exclusive to TOTO. It uses electrolyzed water to premist the toilet bowl between uses. Theoretically, this helps keep the toilet bowl cleaner by preventing fecal matter from sticking to it.  The TOTO S550e also uses EWATER+ to clean the nozzles for an extra layer of sanitizing.

User Presets- The TOTO S550e remote control has the ability to save 2 user presets. These memory settings don’t save every detail of your wash, but they can remember water temperature, spray pressure and nozzle positioning for two individuals.

Feature Bio Bidet DLS TOTO S550e
Adjustable Nozzles Yes Yes
Adjustable Spray Pressure Yes Yes
Adjustable Water Temperature Yes Yes
Self Cleaning Nozzle Yes Yes
UV Sterilization Yes No
Heating System Tankless Tankless
Automatic Seat & Lid Yes Yes
Pulse Mode Yes Yes
Nozzle Oscillation Yes Yes
Heated Seat Yes Yes
Soft Close Lid Yes Yes
Warm Air Dryer Yes Yes
Energy Saving Mode Yes Yes
Wireless Remote Yes Yes
LED Nightlight In Bowl Side of seat
One Button Wash and Dry Yes No
User Presets No Yes
Round Size? No No

Remote Control

The Bio Bidet DLS and TOTO S550e both have dual sided remote controls with basic functionality on the front side, fine tuning on the rear side, and seat and lid controls along the top.

The DLS remote has a horizontal layout with larger push-type buttons on the front.  The TOTO remote is vertical and features touch sensitive buttons with LED accents on the front.

We found both remotes equally easy to use, but the TOTO remote has the slight edge in having more adjustments available without having to remove it from the wall mount. 

Differences in Nozzle Construction

The TOTO S550e uses a single plastic nozzle with different sections for each wash function.  It features an antimicrobial surface and cleans itself with TOTO’s eWater+ system.

In contrast, the Bio Bidet DLS uses a single stainless steel nozzle. It also has different sections for its various functions, but it rinses itself with plain water while sterilizing with its UV light.  

Seat Durability

In regards to seat durability, both the Bio Bidet DLS and TOTO S550e are outstanding.  These are essentially some of the most sturdy seats we’ve found. Both seats are capable of supporting weight of around 400lbs and are built to last. Both the Bio Bidet BB DLS Discovery and TOTO S550e are produced with sturdy polypropylene, glossy plastic and rank highly in durability.


The Bio Bidet DLS Discovery is covered by a 5 Year Manufacturer's Full Warranty:

100% coverage of all parts and labor for the entire bidet for the first 5 years from original date of purchase.

The TOTO S550e Washlet is covered by a 1 Year Manufacturer’s Full Warranty:

100% coverage of all parts and labor from the original date of purchase.

Overall Conclusion

Both the TOTO S550e and Bio Bidet DLS washlets are excellent choices when considering the pinnacle of high end luxury bidet seats. Both the DLS and the S550e have very sleek profiles with unibody designs, high tech sterilization systems, automatic lids and so much more. 

So which one is better for you? If you’re looking to save a bit on the price tag and have the peace of mind from a 5 year warranty, then the DLS may be the seat for you.  If you need the absolute best of the best bidet seat from the world’s leading brand, then the TOTO S550e is the choice. Regardless, we here at BidetKing know you really can’t go wrong with either of these uber luxury bidet seats.