I have the CIPA mirrors. I tow a Jayco 29BHS with a Yukon XL. What I like about the mirrors is the ease of installation and the streamlined look they have once they're on. Very stable as well.
What I don't like as much is adjusting them. Since I am used to power mirrors, I can normally adjust as needed when not towing. With the CIPA mirrors, I try to get it right before the tow starts, but often feel like they are not optimal once on the road and want to adjust them a little. If you have a helper this part is pretty easy to mitigate.
The other thing was getting used to the 2 part picture in the mirrors. You still have the standard mirror, then the extended mirror which has a slightly different field of view. I find my eyes going to the standard mirror first by habit, then having to refocus to the smaller mirror after. That said, the CIPAs do allow a view well to the rear once they are on. I also installed a rear cam in my trailer which helps with lane changes because I can see when I am clear of the vehicle I am passing, for example. Kind of a costly option, though, but I like it.