My opinion: For gravel trails and less hilly commutes - the SL would be perfect. It can tackle both with ease. I ride a lot of gravel/single track trails around my area with my mechanical cycle-cross and the SL handled those without a problem. The fact that you also get to experience more effort than the non-SL could (would likely) be a benefit to a lot of riders, me included. I had a blast riding on the trails with the SL (5.0 btw, with the stem shock). For more hilly commutes and almost strictly commuting (non off-road), I would expect the non-SL Vado to be more beneficial. For that reason, with limited funds and really only the ability to get one e-bike, I chose the non-SL. *FOR ME*, it seems to make more sense to commute with little effort and get to work fresher. When I want to exercise, I will get on my mechanical.