Id full heartedly recomend an acekard over a r4, alot better to use all round, my old r4 is having alot of trouble playing recent games + some older games no matter what firmware i use ect ect.
From the looks of it r4ds.co.uk is the same company as r4i.co.uk (hosted at the same place and both have the same trade name acording to who.is) where my mate ordered his little brother an acekard from last month, it turned up and is working fine (asked him on msn just now), i cant remember where i got mine from as i got it ages ago.
Just be aware not all games will work online (some will) if thats what your buying it for.