I haven't heard anyone loosing warranty by installing an Intake. As long as the part has been installed correctly there shouldn't be any problems. I've done a cai on every car I've ever owned and my dealers never turned me away. And as long as its not the cause of the issue ur brining it in for ur fine.
I feel like I write alot of THAT word "Warranty". Im not an expert and each dealer is different. But here is my take on it. The cold air can technically void the warranty. Most dealers let is slide because the warranty issue you came in with is not related to the intake. Because of a lawsuit from a couple years back, the dealer can only not honor your warranty if the part in question (Intake) caused the issue. So if your SYNC system doesnt work, they cant blame it on the intake. Probably not the best example but you get the idea.
So like Hunter73 said, you should probably talk to your dealer before you install one.
Kind o the same answer as the intake alone, its going to give a couple HP and with the intake you may feel an increase. For under 100 its not a bad buy. Just to clarify it will not work with the afe charge pipe. It pushed the charge pipe out into the radiator shrouding. Given the 2 options I would go with the charge pipe. I think it is a better mod. Install is a pain in the butt on the intercooler pipe.
its not bad if you do it on a lift. Thats how we did it. You really just need the angle right and then it slides right up to the TB. Im not sure you could do it with the truck sitting in the driveway and not up on jacks.