1. Not me. The original software was a pile of cack as I recall. I did have a Netgear storage router that came with the software installed. That was OK since it saved me loading some software: on the downside, it was like going back to the dark ages compared with Media Centre.
2. Do you mean 1.4.7? It's not been officially released, to my knowledge, but it's readily available (let me know if you want it). I'm sure I've seen somewhere that it does nothing for the Vista problems, but I could be wrong (I'm sticking to XP for now). Sorted a couple of things for me, but you need to be able to power cycle your MP101 to live with it (it hangs after a couple of hours of inactivity).
3. They go for a fair bit. I wait for an unpopular auction and reckon you can get them for £20-25 with a following wind. Bargain, IMO.
4. I reckon you have to choose between your MP101s and Vista. Sorry, but it will be hours less hassle for you.
Mark.