Help! Is my clutch slipping?

mastersapo

To start with:

2010 370z, manual Trans, 28k miles. I am the sole owner of this car, I got it with 6 miles. Slightly modified with intakes and the Bully Dog tuner (WOT and performance tune)

What's happening:
Recently I noticed that in 4th, 5th, and even 6th gears between 2500 and 3500 rpms, I can stomp the peddle and the RPMs will very quickly shoot up about 1000 RPMs and drop 500 before it accelerates (sort of like feathering the clutch while accelerating). When this happens, my foot is nowhere near the clutch so I know I'm not lazy footing it. This is happening very quickly, but I believe my clutch to be slipping or partially engaged. Does this sound accurate?

2nd issue: I live in Orlando (not from here originally) and have no idea where to take it to get a good clutch replacement. Honestly, I would probably have an aftermarket kit put in, but again I have no idea where to take it and I absolutely do not trust Nissan dealers. I have had problems before that they never fixed (clutch getting stuck in after a high rpm drop in 1st, rear trunk latch not unlocking, etc... basically the worst car I have ever owned). No lift or I would swap it myself. Is this something I could go to like an AAMCO or dealer for and feel safe?