Looking for ideas or what I should look out for

Hello everyone, I’m coming from a mk6 Jetta Gli. My vw has been great and I’ve loved owning it but I’m looking to part ways with it. The car is definitely quick but I’m looking for something a little bit faster. I’ve already don’t a crap ton of research on the n54 and n55 engines but I want to hear from actual people with real cars not just built from the ground up. From your experience how has reliability been for your car? And what would you say are some red flags to watch out for when trying to buy one of these beautiful vehicles?