I love the ergonomics, fits my hand better than almost any other pistol. I prefer the trigger over the M&P since it feels more "solid". The MP feels a little mushier to me. (however mine needed a bit of polishing to be really smooth, but then my standard for triggers is quite high)
The sights take a little practice, however I found if you ONLY focus/concentrate on the front sight, (basically ignore the rear sight) it become very natural and extremely fast pointing. If you have used a fibre optic front sight before (again, it emphasizes use of the front sight) you won't have any trouble.
Can't comment on reliability as we haven't used it too much (yet), but so far, it has been fine.
As for a tight chamber, all of our reloads are run through a Lee Factory Crimp die as the last (4th) die, and it has a carbide sizer to again size the finished round, so even glock fired brass has never been a problem.