I'm also shooting out of a sub-4.5" gun. It's a Walther PPQ. Pretty comparable to a Glock 19, if that helps you picture it. I hadn't heard anything about barrel length for the Critical Duty. I am intrigued, though.
I would shoot the critical defense line, but I like a heavier bullet for self-defense -- just personal preference based on my limited self-education on the subject. Really, my opinion is: I wouldn't want to get hit by either one. Heck, I wouldn't want to get hit by a .22LR, for that matter. But, when the adrenaline is pumping, it would be nice to have the laws of physics on my side. Typical 124gr JHPs and the 135gr Critical Duty seem to have a good velocity / bullet weight ratio. Even some of the newer 145gr JHPs are starting to perform really well.
Anyway... DE Guns, of course! I should have thought about a special order through them. I really like that store. I'll ask next time I'm there
drooling looking at their inventory.
Thanks!