I purchased an XL frame, but added 700 x 45c tires from Specialized to improve comfort. The seat on the Vado SL 4.0, is one of the best I have ever ridden as a stock saddle. It is extremely comfortable on long rides. The grips are fine, but I upgraded them to a thicker set, as my hands are rather large. This bike as advertised, rides just like a normal bike, even with the power completely off, you can still pedal easily, and there is zero drag from the motor. Truly, Specialized engineered something really special with the SL. It is also fast, very fast, and getting up to 20mph or so, is not difficult. The 35nm of power are fine too, since the bike is not that heavy, although, if you are looking for a strong push from a motor, this might not be the ideal e-bike for you. The power seems to come on smoothly. I ride mostly in Eco mode, which yields an average of 70 miles per full charge, which in my estimation is pretty great. Occasionally, just for fun, I will ride in Sport mode, which gives me about 35 miles on a full charge. On my 40 mile normal round trip jaunts, I sparingly will use Sport mode, just to get up a steep hill, but never ever use Turbo. I am also a large frame guy, 6’3 and weighing north of 250 lbs. The SL seems to want to ride fast all the time and handles very well. After 2 months of ownership, this is probably one of the best bikes I have ever purchased. A quick word on the aluminum front fork. I was very hesitant to purchase a bicycle without a suspension fork or carbon fork, as I had a very bad experience with a 2002 Trek road bike, which had an aluminum fork. Technology has improved, and in addition, the 45c tires certainly help with comfort. Yet on long rides, my hands and wrists are fine, no pain or numbness. I do ride with cycling gloves all the time. So for the money, I would choose the 4.0 over the 5.0.