I have the zipp SL-70s on the trainer bike and these on my favorite outside road bike. Both are VERY new- only aluminum on my bikes until January of this year. It's fair to say that both are high quality bars of course, both offer SOME shockvibration-dampening but I cannot say that i've seen a dramatic difference in fatigue over round alloy. Possibly round carbon does a better job. I stopped riding with gloves 10 years ago and I still ride rather thin bar tape. Stiffness is great. I am a sprinter generally and both the Enve's and the SL-70s do well here. I can't do a TRUE apples-to-apples because they're not the same size. And that size seems to be a very contentious discussion. Without instigating a whole argument about wide versus narrow, I will simply state, my sl-70s we're purchased before I understood their flare. They are 40s at the hoods measuring about 41.5 at the drops. I bought the Enve's in 40 (on purpose) which are 36 at the hoods and curved in. I LOVE THEM. I like how they bring my elbows in. Definitely more aero- no comfort trade-off I can find. But let me also add, that switching back and forth between the two bars has literally been a non-issue. NO adjustment. I don't even notice. I also wanted more reach. The Enve's are 79 (you may see advertising otherwise- they're marked 79 on the bars), the sl-70s are 70. I like that extra length for my wrists slapped down behind the hoods. Both bars clamp well and stay in place including the brifters. I use a pretty basic aluminum stem on both bikes. I had one frustration with the Enve's - cable routing. I don't know if I just got one that was a little rough on the inside but the Enve's ripped apart the brake housing of the first pass I made through with an old cable for testing. And VERY hard to get out of the hole by the stem. The sl-70s are SO FAR AHEAD here. But after fiddling with a test section of housing on both sides, I managed to build a little bit of technique that reduced the effort and didn't ruin the real set of cables. If you're running mechanical- good luck with the Enves! I do on the SL-70s (Shimano DA) and both shift and break go nicely in one hole and come out by the stem together beautifully. I have no idea how you would get them both in one hole on the Enve's with all the trouble I had with brake cable only (Gen1 Etap). I'm very interested also to try the Enve clip-ons. (aero bars)- another reason I was attracted to the Enves. Oh, I've seen no one comment on the bar end plugs. They're ok. Frankly, no big deal-- until you break one since without sawing off the ends, the openings are too small for standard bar-end plugs!!
First of all, I really like the ENVE compact bars and the SES Aero bars are a bit of a departure. The flat platform is very comfortable on the hands when riding the tops, and the flare actually makes riding deep in the drops more comfortable on the wrists. They are very aero and put your arms in a more streamlined position. As it turns out, I didnt need as wide of a bar as I thought. The internally routed cables make the nine look really clean. What I dont like as much when comparing the Aeros to the compact bars they are too narrow due to the flare and I still had to size up (the 46cm bars are 41cm at the hoods), they are noticeably more rigid and dont seem to dampen the bumps as much, and you have to to chop the bar ends in order to install the junction box which sacrifices some of the drop length.