Have a look at the Boardmans in Halfords, good quality bikes with good spec and lightweight.
Ive done the bike2work scheme twice now through halfords as our company run the scheme every two years, my 1st was a 1k Boardman ht pro, fantastic bike that it was, i covered 3400 miles on it in the 2yrs i owned it. The only faults that occurred was the BB failing 3 times. After the 2yrs i sold it on for £430. The 2nd bike which is my current on is the 1k Team FS, ive had it since July last year and done 1700+ miles on it, this one has had a few niggley problems but halfords sorted them straight away IE the freehub has packed up twice, and the back end came loose once.
The way i use the scheme is to treat all the bikes i get as disposable, I run them for 2yrs spending as little as possible on them, then i get rid before anything major goes wrong, that way i can recoup some of the money i spent buying the bike. The HT Pro was 1k but through my wages it worked out at around £630 due to the discount, then add the final value fee which i think was £100 at the time, so all in the bike cost me £730, then knock off the £430 i got for it when i sold it and basically ive rode a nice lightweight hardtail for for two years for £300 not including consumables.
One thing i will say is please dont abuse the scheme because if it gets abused by to many then the scheme will be stopped by the government. Then i wont be able to get a new one http://www.halfords.com/webapp/wcs/stor ... 65499#tab2