speaking as someone who went through the Helicopter Services system in the not too distant past, they have a wealth of experience for the courses they run and agree Leon has a good setup. (he doesn't like Geordies anymore tho!!) They may get you up to standard but it's up to you to pass the test. I let them down on their pass rate unfortunately, but after a 'couple' of attempts, got through the IRT with them.
The key to the whole training industry is research. Go through every resource you can find. Speak to as many people as you can who may be able to recommend somewhere and search the internet, ie PPRuNe.
Ask the pro's where they would recommend. Cheap courses are usually cheap for a reason. Advertised at a lower price then more training necessary to get you up to standard perhaps? No, that doesn't happen. Shouldn't have said that.