Yes I have a Ferm SDS bought from Srewfix several years ago, it was a cheap brand they used to stock, cost about £30 and had a two year warranty. It hasn't had a lot of use but has performed well and I have just removed a tile floor and cleaned up the old cement/grout with it.
I got a set of bits of e-bay, Blackspur brand, consisiting of a gouge, spike, chisel, electrians chisel and a 80mm tile chisel for 13.96 in P&P. The company was tooltime.
It depends on the use you expect to give the kit. If its going to be heavy usage on a regular basis its probably worth buying something upmarket, if the use is low a cheap one will last a fair while and anyway if you have expensive stuff and it fails after the normal one year warranty I'd be pretty gutted.
How do you get 20% off at B&Q? I can only get my Wednesday old git discount.
Wickes do a range of power tool woth 1, 3 & 5 year warranties, has anybody an experience of their kit and more importantly how good the warranty is if things do go wrong?