I'd agree on the whole American RT is pretty poor in comparrison to UK RT
It could be argued that its maybe a little too rigid back home. But here 'errm, Seneca no sorry, Cessna 121BM, 3,250 feet with Juliet Information, looking to land at the airport, needing taxi progressive upon landing, do you have a pilot shop? Thanks', also on tower frequency 'Just cleared the active runway and it'd be nice if I could taxi back?' isn't that uncommon.
I'm lucky to be training in very busy airspace with Bravo, Charlie and Delta airports almost touching each other. I'm also being instucted by a CFI/CFII/MEI with both JAA and FAA instructor ratings. So my RT will be to UK standard even though I'll have to do an RT exam before flying iin the UK.
Essentially what I'm saying is that as long as you do your homework with respect to the location of the school and the background of the instructor then you shouldn't have any issues. Just identify where you are going to do the majority of your flying and plan around that. A £3000 PPL in the US might end up costing another £3000 in the UK when you have to undo bad habits and bring the standards up if you don't choose where you go with enough consideration.