Simply the best available today! I'm a 60 year old who can keep up with the Peloton on Day 1 (Saturday), but my increased recovery times mean I always find myself in a slug fest on Day 2 (Sunday). This bike takes that factor away - even if you don't use the assist, the peace of mind it gives you gets you out there on Day 2 even if the course is hillier than usual or it is windy. I've owned other high-end e-bikes - no other propulsion system comes close to this - it's smooth, silent, responds to your torque input, and goes forever. The cons - the price, of course. Disappointing to not have a fully integrated cockpit at this price point, no bottle cage although shipped otherwise extremely complete, and why is it geared as a gravel bike? I will be swapping out my 10-30 SRAM Red cassette. Putting that in context - when you look at, ride or own something else like the Mahle, Bosch, or Fazua systems, this drive system more than compensates for the few adjustments you might make. Do you need the S-Works version of this bike? Probably not. The Expert is nearly the same, heavier groupset and other components, which won't matter much if you tweak in the assist level with Specialized's truly ground-breaking "Mission Control" app - again, something you don't get with some of the competitors. For me, having the S-Works version was my entering argument - not based on logic. Hopefully other readers will find this helpful.