There are many factors that go into the go/no-go decision under IFR. I mentioned a few. But I think it would simply result in another interminable thread, trying to answer a question which was never posed.
There is a strategy for the JAA IR which is to revise a bit, sit all the 7 exams in one go (over a day or two), and then revise properly for those which one fails. However, this works only for experienced pilots who already know about flying and IFR e.g. FAA IR holders. A totally ab initio pilot is going to have to swat for months and months, and anyway he will have the mandatory classroom attendance.
This is why the FAA IR / N-reg route is attractive. Many many pilots have followed this. You start with a UK PPL, IMC Rating, buy a plane, do a lot of IFR flying and get good, then go to the USA and do the FAA IR (and a standalone FAA PPL) in something like 2 weeks and 20-25hrs of flying under the hood.
Advantages of this route is that you can do the IMCR at the same old school near to where you live, and you get immediate (UK only) IFR rights which allow you to fly IFR, and to fly VMC on top into Europe (a key privilege for practical VFR touring). And when you do the FAA IR you get full credit for all IMCR training.
Whereas the JAA IR gives you zero credit for any previous training - unless you have an ICAO (e.g. FAA) IR in which case the 50/55 hrs min flying time reduces to 15hrs and the mandatory classroom attendance goes away.
The current EASA cage-rattling makes the FAA route more uncertain but as an overall route to the JAA IR it remains completely valid, due to the massive training credits
- IMCR training counts towards the FAA IR, and
- the FAA IR reduces the JAA IR min training time from 50/55 (SE/ME) to 15hrs
- the mandatory classroom on the JAA IR is eliminated
and obviously one would move to the JAA IR only when (if) EASA really is going to shaft foreign licensed pilots. The earliest likely date seems to be 2012.
The downside of the FAA route is that an N-reg plane is needed to get the worldwide IFR privileges. This has advantages though, in various respects.
Training in the USA is also much cheaper. My IR over there cost me about $3000, for ~ 25hrs. Plus another $1500 for the motel and flights. Considering the JAA IR gives no credit for any previous training, if you did the 50/55 hrs here (can't do it in the USA) it would cost a huge pile more.
Just another perspective....