the club is black park model boat club near slough ( we actually back onto pinewood studios) and you could probably whizz up the M4 on a sunday morning in under the hour !- the lake is pretty damm big, the water is pretty clear ( however if you go to deep there is the risk of some weeds) however most weekenda you will see subs and surface craft sailing with no problems....
for more details PM me or see
www.blackparkmodelboatclub.co.uk
there is some pictures of some of the subs that gathered for the discovery channel filming too.....