It pretty much depends on how you drive. As my DD, most of my drive is stop and go city driving so high performance is a non-issue. I also don't want a loud exhaust or aftermarket exhaust resonance. I did buy a Remus axleback exhaust, because at the time I thought that would be necessary for the P2 tune (it wasn't and isn't) but sure enough, there was resonance. I have a complete thread on dealing with Resonance and a Remus exhaust here if you would like to look at it
Dampening Resonance with a Remus Exhaust but if you want the short version, it turns out the resonance was primarily caused by the actual exhaust tips not extending out behind the car. The tips that you get from the factory are fake, and are literally bolted to the back of the car. The Remus exhaust barely extended into the inside back of them, so the sound coming out of the exhaust tips was coming out into the inside of the back of the car. This caused the back of the car to resonate up into the trunk, which caused resonance in two major areas; the aluminum heat shield, and the black box in the middle of the trunk. It wasn't until after I went to the trouble adding dampening mat to those areas in the trunk (which helped but not enough) that I figured out the exhaust tip issue. I bought actual exhaust tips, removed the fake factory tips, and attached the actual tips onto the ends of the exhaust so they actually extended out behind the car. Problem solved; resonance gone. At this point I can't say if that alone would have solved it because I didn't do that until after adding dampening mat, but it was what finally eliminated the resonance.
The interior noise level under normal driving is no worse than it was stock, but when you accelerate you can hear the extra growl of the exhaust which is fine. Cruising along on the way to work I can listen to the radio or music without any interference from exhaust noise. For some people, that's not what they want. They want a loud exhaust. I wanted the improvement in performance, and it did help. Adding just the intake smoothed out the low speed performance noticeably. Gradual acceleration was smoother, easier, and the trans shifting wasn't as jerky. Under normal use, I don't notice the intake noise; this is with windows rolled up. Rolled down, you can hear it when you accelerate. Rolled up, you can still hear it slightly when you accelerate, but I've gotten so used to it I don't even notice it now because it's in combination with the exhaust growl. I actually like it, sounds good.
When I'm running the stock tune after flashing the car back to take it into service, I can tell the tune isn't there. You don't notice anything when you first accelerate, but you notice it the moment the trans shifts into third and beyond. The car doesn't pull nearly as strong as it does with the tune. (This is with their V2 intake and a Remus exhaust). Floor it, and you definitely notice the difference. Compared to having the tune, it feels like I'm pushing against a headwind; it just doesn't seem to want to pull and go like it does with the tune. I have two stages of the tune. I have Phase 1 (P1) in N mode which I use for daily driving, and is a very nice improvement for that kind of driving. When I need more, I switch it to D mode which has Phase 2 (P2) on it, and it transforms the car very noticeably. It feels like the car hunkers down about an inch, the trans shifts down one gear, and the throttle response is more aggressive. It's clearly better than the stock tune.
The question is, is it award-winning, record-breaking, OMG performance? No. It's not going to transform your 2.0 into a QV. It just isn't. If that's what you're looking for, the tune isn't going to deliver that. At least by itself. If you want to start throwing money into mods and begin upgrading intakes, exhausts, downpipes, lighter wheels, brakes, etc. and THEN get the tune, yeah it will be pretty impressive. Still won't be a QV though unless you really throw money into it, but if you're going to do that, just get a QV.
If you have the budget and can afford it, the EC tune is really really nice. Even more so if you add the intake and an exhaust. You can even add those later and they'll adjust the tune for you to take advantage of them. Do understand though, that these cars learn any changes, and it can take a bit before the full benefits become apparent. If you have any questions or concerns, the people at EC will be more than happy to go over them with you and help you.