Can't question the power. To me personally, I don't think it offers enough of an advantage over 10 mm (or even .40 S&W, see below), as 10 mm beats it with heavier bullets and offers another round of capacity in the same size gun. Of course if you had a .45 it could be converted just with a drop in barrel and recoil spring, so it would be a way to get 10 mm power with little expense.....except for the ammo. Hard to find and expensive. You could reload, but for all the advantage the bottleneck supposedly gives in feeding (I don't see this as a big deal, personally), you have additional issues of possible setback, shoulder length, etc. If you can find reloading data, I think you'd be surprised at the pressures listed. Some older Accurate data listed max pressure at 29,500, and it wasn't quite getting the performance of the 10 mm which was admittedly at 37,500 max pressure.
In regard to the .40 S&W, here's something interesting: Vihta Vuori
lists a max load for not one but two powders in the .40 S&W that are getting 1360+ fps with a 135 out of their 5.5" barrel. Although I haven't shot those particular loads, I have found their velocities to be entirely realistic, if not conservative and able to be reached in a 5" barrel. Corbon actually claims 1325 for their 135 gr. .40 S&W factory load, and I have read that it has chronoed 1280+ out of a Glock 27. That's not a big difference to me, and the package is smaller. Just my $.02.