Where are you guys coming up with $10k for aero???
I know that I can come up with a good (not great and top of the line) but definatly good set-up for between $2k and $3k not including install.
Yeah there's going to be some tuning to get the suspension dialed in again but $10k seems a little out there to me - I guess if you take it to a shop and have them install the best stuff around and get it dialed in you could hit that number but $10k seems high to me, it can be done for much less especially if you don't mind doing some of the work yourself. Just sayin
I do think that the aero is worth it at most tracks.
Coil-over's are much easier to test and tune with (you have a much better selection of springs to choose from and to set them up properly it takes less time to swap them out).
Yes the RAFT cars make leafs work but unless you are taking it to Danny don't think you will get the same results they do. Both leafs and coils work can/will work well but I find coils much easier to work with.