I bought a clean-ish low mileage RSX just under a year ago, there are a lot of issues that can arise on an old car like an RSX if you aren't intending to spend a lot of money on it. Don't worry about the drivetrain (if you buy low mileage with a good history), it's the items surrounding the engine that will fall apart. I love the car and it is a fun car to start working on as a first car. If you are looking for a type-s you might have some issues finding a low mileage clean example, which is what I would suggest. If you can drive a manual, buy that if you plan on doing any mods later on. I bought an automatic and I wish it had been a manual. Also, I probably wouldn't suggest buying an RSX with the intent of modding it and then selling it. Modded cars don't sell for as much as you put in, only mod if you intend to enjoy them.
Overall, I would suggest it as a first car. It isn't the fastest car out there or the most technologically advanced, but it drives great and is fun to own and work on.