I'm not sure if you guys own an 09 or above, but a simple stage 1 tune (torqued performance) makes the car 100x better. I honestly wasn't happy with the car stock (the stock tune is just THAT bad). It felt like I was driving a civic. No torque, hesitation, hiccups, etc. I honestly can't believe subaru has such a crap tune.
But for me, taking the risk with a stage 1 tune is 100% worth it to me. I spent 30k on a car and if I left it stock I'd be driving around a 30k car that I didn't like. Now I have a 30k car that I love. From hate to love with a simple stage 1 tune. That's how bad the stock tune is.
That said, If I ever need to take it in for warranty work I'm just going to leave as is. If it's denied because of the tune, oh well, my fault. It's a risk I'm willing to take. It's the difference between enjoying the car or not.
But I still don't get why so many people on this forum give others a hard time when they ask warranty questions with a tune. What is wrong with someone wanting to still have the warranty they deserve on a 30k car, AND having a car that FEELS like it's worth 30k (after the tune)? I completely understand the warranty can be denied, but it's not necessary to bash anyone who has questions regarding warranty/tune issues.