Mike, if you're looking for a set of quality bits for metal I'd be surprised if you'd be satisfied with the 'bargain' (under 7 quid) offerings at UKDrills. I have bought sets at a similar price point and they're pretty much useless for drilling steel, though OKish for brass provided you're not too fussy about the actual size of the hole...
Depends on how many holes you want to drill in what obviously, but my experience has been that it's worth paying more for 'industrial' brands - Dormer and Guhring are excellent, but I've also got cheaper Presto (various suppliers) and Sherwood (Cromwell Tools) sets. They just work.
Robin