Some one a long time ago asked about the X-Bit chip from DMS? Well, I don't know if anyone cares, but here goes. i have installed that chip on two Xboxs and I am about to do it again on a third. The first two times I bought it from thr UK, now I am waiting to buy it from USA (cheaper).
It's installation is a breeze. Just make sure the pins are lined up right. When I load the bios in, I like to change the boot screen so i know that it is on. I have bad soldering skills (but they are inmproving) so that is the main reason I liked this chip, plus, it has usb, which makes it a breeze to flash.
A guy I knew had trouble installing one, so much in fact, that he sold it too a friend of mine for 30 bucks. I installed the chip with no problem on my friends box. So, all in all, I like the chip. We have no problems with it, the xbox gets moved around a lot and it works great. So, yeah, that is that.
I don't think there is anything to secial about any of them, in my opionion. Although, the ones that have ntwork/hdd activity sound appealing to me.