Glock 20C

Quick summary of the Pros/Cons for the Glock 20C:


Pros:
-Reliable (not a single failure to date)
-Accurate (more accurate than 99% of the shooters that own one)
-Durable (10mm Glocks seem to do better than their competition [EAA/1911/ect...] in handling the 10mm wear)
-Easy to maintain
-TONS of aftermarket support
-15+1 capacity
-Glock's customer service is great
-Durable finish
-Cheap replacement parts, should you ever need them
-Low Bore Axis resulting in a relatively soft shooting gun
-Easily modified to fit the shooters' preferences
-Requires very little cleaning/lubrication to run reliably
-Muzzle flip and perceived recoil are minimized vs the standard G20 allowing for faster follow up shots

Cons:
-The C model is much louder
-The ported barrel may make your front sight turn black (mine doesn't seem to but I've seen others that do it after 2 or 3 rounds)
-The ported barrel causes a decrease in muzzle velocity
Here's a video comparing with some shooting and a comparison to my Gen4 G20:

http://www.youtube.com/watch?v=rDdTdJbv80Q