I have tried the Koobi but wasn't impressed. I have not used the MTB Cobb saddles but have tried a road one and it was quite good. My preference is for the ISM Adamo saddles which are also designed by Cobb. I would try the Cobb or an Adamo Peak. The Adamo needs a bit of adaptation time and is wider through the nose than Cobb. They are also heavier but not prohibitive.
The reason i didnt end up with the adamo on my list was for 2 reasons.. Wider front(could cause chaffing) and longer in the rear(hard to get off the back without getting hung up on the back lip)...I was very close to pulling the trigger on the koobi-- but looking around last night and hearing you say the cobb isnt too wide -- im thinking i might just go for the cobb..
Well I don't think the Adamo is too wide, just something that takes adjustment. The Cobb is not much different than other saddles in that regard. Getting off the back with an Adamo is not an issue. It's possible to hang clothing on it but that's possible on any saddle. I actually have more trouble hanging shorts up on the nose since it's wider than normal. The rear gives me no problems at all.
I have a Koobi Au Enduro and find it the most comfortable saddle I've tried on my road bike (which is the real test of a saddle's comfort, IMO). I would run one on my MTB, but the back is wider than I like on a mt bike.
It is wearing out after about 10 years, and I will be getting another Koobi.
15mm is a second-best solution to a problem that was already solved.
The koobi century looks to be a little bit narrower vs the enduro.. Even though it says there is only a 2 mm difference-- if you look at the pics it sure looks to be more then 2mm.. Im going to call cobb tomorrow and see how wide the drt plus is... I leaning towards the cobb right now but who knows what will happen between now and order time..