Finding the right monitors isn't easy (unless you have an unlimited budget of course!) And unfortunately, listening tests in a
music store might not tell you much either -- my dumb ears have in the past gravitated towards the monitor with the highest sound pressure level or the most high/low-end presence in a side by side test, even if it is not the most accurate or cleanest.
For what its worth, I've heard those red Tannoy's (forget the model) are probably one of the best values out there. I got away with abusing an old pair of that speaker's bass-lacking predecessor, the PBM6.5, for a long time. Event PB8's are in that range too -- but for me they were hard to mix on, seemed like the lows and highs were exagerated and there were holes in the mids or something... I dunno, IMHO the Tannoy's would probably serve you well in the long run (moreso than the NS-10M's at least, especially since your ear isn't "tuned" to them yet!)
Maybe it doesn't even matter -- JEM's probably sound great played back through all of them!