2006 325i

[HENDO81]

Hey everyone, I'm new to the forums and I just had a few quick questions. This past weekend I purchased a CPO 2006 325i (my first BMW, which I LOVE so far).

1) What grade of oil do most of yall have in your BMW and how often do you have it changed (I know the standard is 10k, right?)?
2) Do yall recommend any aftermarket parts? I'm currently looking into an alarm system, would it be beneficial to have the dealership install one (even thought I'm sure it will cost more)?
3) I've heard the RTF's aren't so great... any recommendations on what to replace them with when the time comes?
4) Any additional advice for a first time BMW owner would be awesome :)

Thanks guys!

[Kredithai]

If you really want the alarm, let the stealership do the work.

Go with Continental SSR's or Pirelli P Zero run flats, both are infinitely better than the stock rubber.

[Edison@Jlevi SW]

For the alarm, DIY the install and have the dealer flash it for you. They are going to charge a bunch to install it when it's something you can do on your own.