Having seen quite a lot of the really cheap duel suspension bikes on hukd recently several people have asked for a recommendation for a 'cheap' but good mountain bike.
I bought two of these from Tredz (mans and womens) and I think value for money they are unbeatable (also won Mountain Bike Radars best in price award, think it was in the under £400 bracket).
The disc brakles are amazing, stop on a sixpence, and the general build quality and overall specification is incredible in this price range.
If I had to fault one thing it would be the slightly cheapo front suspension fork, but that would be very critical.
As a final note Tredz have a fantastic customer service and were very helpful when I dealt with them.
Hope this might help some people looking for a good value mountain bike.
I think this is probably the best current price.