Well, the appeal (to me), is:
1) Being different. Sure, its not like you see 3Ls with P90 heads and turbos very often, let alone 240s at all in the central valley that are actually on the road, but it is different from the norm.
2) Different kind of labor that has to be done: Instead of having to pull the entire head assembly, AND do all the piping, so far it seems like this setup would mostly just need the piping redone.
3) My current setup was built by rebello, and probably is worth more than I paid for the car when you include labor, so if at all possible I would like to keep it the way it is (mostly).
Sure, there are some things that will make it more difficult to do than a straight head swap etc, but there are other things that matter to me (like keeping computers as far away from my engine as possible).
*shrugs*, thats just me.