I bought a dream genii a few weeks ago (my friend had been going on about how good it was), I bought it for £23 from amazon (think they were price matching a offer at Boots - sorry, think it may have expired now though), I thought for that price it was worth a punt - so far have used it about 3 nights on and off (my bump is still fairly "compact"), and to try and help me not sleep on my back (it's soo hard not to do!).
My thoughts so far... I can see how it helps support the bump when I get a bit bigger and it's quite "comforting" how it wraps around your tummy and back, and I think to some extent does stop me moving so much in the night, but I have to say, so far I'm not totally convinced. I appreciate this may change with increasing size of bump...
oh, and for anyone that uses amazon (I know it's a personal preference thing), a useful website to know about is uk.camelcamelcamel.com/ you can look up how much items have cost on amazon over time, and you can also set price alerts so when an item reduces to that price, you get an email.
Hope it helps someone!
TM 16+3