I've actually read a review where it was getting pretty nice overclocks (280MHz) with good timings. This was for the pqi Turbo, which is pretty cheap. The stuff I was reading about used Brainpower PCBs and TCCDs. There are different releases, though, and I dont know if all pqi Turbo uses BP and TCCD.
But thats kinda off-topic in relation to the original post. Sorry Mafy