Upgrading Verizon Diamond

[bliind]

A friend of mine got a Diamond after seeing all the fun I was having with my TP, but unfortunately, he has Verizon. I've searched plenty and I've found that there's no unlocker for the vz Diamond (though why, I'm still not sure).

So my question is, is there any sort of ROM I can put on his phone that will treat it better than VZ's rom (which is ugly and slow, imo)? I've checked HTC, but I didn't see any ROM releases for the vzw version, and I've browsed both here and XDA pretty diligently. And to top it off, I checked Google, but to no avail..

Thanks in advance..