Yeah, I would say that I've never seen a modchip directly kill a PS2. What has killed the PS2s I've run across is bad media and scratched discs, and even then the lasers can be replaced. Bad soldering has been the culprit in a few I've seen as well. Too much heat applied to traces and chips during installs will also kill them - if not right away, slowly over time you'll see issues.
I think as long as you stay away from clones and go with either a Matrix Infinity or Crystal Chip, you'll be very happy. The Matrix gives you more control over some stuff without using a Boot Manager, while the CC uses a Boot Manager for a majority of it's features - but it has a ton more features and abilities. So, it all depends on what you're going to do with it I guess.
Modding in Denver, CO and surrounding burbs