Something perhaps worth to be mentionned: when I had my guruplug on wifi client mode, I used it as a music server running mpd so it was basically hooked up on the network only to receive commands from mpd clients and this way it could remain stable for days, but as soon as I used it for heavy download traffic, it usually crashed within minutes.
I'd appreciate if someone else can confirm this: the guruplug in wifi client mode is unstable only if there's some network activity.
I think this could rule out the heat factor. Besides, I'm actually having my guruplug unrar a 4gb file, while downloading torrents and streaming music (on ethernet of course); the cpu is near 99% usage and no crash yet.
Meanwhile, I have contacted globalscale and marvell, no one seems to care. YAY