He's been supercharged the entire time though. That's a major difference over being n/a for 300k+ miles then deciding to throw boost at it
I remember some user on here put on a s/c at around 300k, and despite his compression checking out great beforehand, it only lasted 10k miles before the motor cracked a head/blew a head gasket and killed itself
It's a gamble flat-out, no other way to put it. It's a risky maneuver that might pay out well, or it might screw you severely, and there's no way to find out unless you do it. Doing a compression test will at least give you an idea on the life of your piston rings and valve sealing, and whether or not you even have a fighting chance, but things like the integrity of your head gaskets and transmission are all still up in the air and just as crucial
It's a good sign it runs less boost than before and will reduce all this strain slightly, but is it low enough to be negligible for your car? Who knows, that's part of the gamble. People like to say "it's not permanent, you can take it off if you have problems" but that only goes so far and really doesn't help you with any serious damage that can happen
If it's not your only vehicle and you can afford an engine/trans swap worst-case-scenario, I'd say do it anyways. Otherwise I'd really think twice. I'm at 317k and have been wanting to add a s/c for a while now but this is my only vehicle and it would really suck to blow it up, so I'm playing it safe and staying n/a. Which really sucks, but doesn't suck as bad as buying a new car. I've heard some people say they're much harder on the trans than the engine, and idk how much I believe that since the A340F is pretty damn stout, but it was still enough to spook me