Buying a Gen5 Manual

Hi all, I am test driving a 2010, 2011, and 2015 all with the LS3 and the M6. Is there anything specific I should be checking for? All are around 70k miles, give or take. I’ve read something about the shift from first to second being sticky when it’s cold but that’s about it, and I cannot confirm the validity of that lol

I just wanted to get some pointers before I go this weekend with my scanner and test drive them. The computer can tell me codes but I wanna make sure everything feels right too.