The overclocking is sweet. I've been been using it for a week now @ 710.4 Mhz. The only lockups I have had were when I boot into Android. I move SetCpuSpeed.lnk out of Startup and soft reset the phone to turn OC off...then I run Haret.exe.
If you are into Android, I would recommend checking out Neopeek's ROMs and web site.
http://forum.ppcgeeks.com/cdma-tp-up...s-neopeek.html
Neopeek - Network
His ROMs use an ext2 (Linux) partition on your SD card. The more recent versions have a zip file that include everything you need and are very stable. My only issue is getting bluetooth to pair with my Jawbone headset, but that's an issue I have with XANDROID ROMs too.
Good luck.