I've got one of these as my test board. It's currently churning out 400 MH/sec. I use it to flash BIOSes of 6950s.
For the OP - this particular board (mine is the E35M1-M without the 'Pro' - the Pro simply runs the CPU faster and has a fan on the CPU heatsink, whereas the non-Pro doesn't have a CPU fan, just a heatsink) has the CPU / GPU soldered to the logic board. It's all integrated, and the non-Pro version (mine) only has a passive heatsink on the main chip (AMD call it the 'Hudson' core, and also anything including CPU, ALU, GPU - it does all of the functions).
I think I paid around £80 for the board. This is a microATX logic board, AMD Hudson CPU / GPU included, fanless heatsink, and memory. Basically, an entire PC ready to go, just add hard drive and power supply.
It has two PCIe slots. One full length x16, one x1. To use the x1, you need a PCIe extender. Both work using extenders.
I've stuck an old CPU fan on top of the heatsink for safety, but it rarely uses much CPU anyway. It's a very cost effective 'test' rig for Bitcoin mining.
However, if you plan to quit mining at some point, and then use the machine (with its monster GPUs) as a gaming box, you'll find that this particular option will be horribly underpowered in the CPU department. It's only of use as a casual machine, or for an application that only requires GPU power.
Mine has also been VERY reliable. Linux *does* make some snarky remarks about the Hudson CPU in the kern.log so I assume it's tricky in some way and needs driver tweaks. However, this board is the ONLY machine I own that has a native Windows installation - I'm using XP because the GPU BIOS editing and flashing apps are only available on Windows or DOS. Windows works well enough (as far as I can tell) on the board, and since I use Linux for mining, I can vouch for the board working well with both operating systems. It won't run OS X though, AFAICT.