I currently own this phone, but it's taken a beating and it's time for a new one.
I've located a replacement online, but I also found an unlocked V9x for about the same price. Is there any reason for me to switch to the V9x or is the V8 infinitely superior? I've never tried out a p2k05 phone so I really have no frame of reference.
Really depends what you want.
If you are after modding and changing looks and features then the Linux based V8 is the better choice, if you just want to change the look then the V9x will do.
I personally had some experience with P2K, P2K05 and Linux Motos, but would prefer the Linux one over the P2K/P2K05 ones any time, but this is just my personal opinion.