Sorry to disagree, Tinstaafl, but don't get a Jep. Get a CRP5.
For all practical purposes, they'll do the same thing. But for the ATPL exams, you'll find that some of the multi-choice answers are very close together. You'll have to be extremely accurate to come up with the same answer as the examiner. The thing is, the examiner uses a CRP5. These things are not perfect, and if you use a Jep you might (I'm not saying you will, just that you might) find that you get an answer which is different. Not so different that it would have any practical effect on your flight plan, but it might just push you into the "wrong" answer to an exam question.
Also, the instructors on all the ATPL ground-schools will use a CRP5 to demonstrate on, so if you have anything different and you're not 100% sure how to use it, you might struggle.
I know the CRP5 isn't cheap... but if you get one second-hand, it looks like it can cost the price of 1/2-hour in a PA28 - hardly a big deal when you look at the total cost of getting a PPL, let alone an ATPL(f).
(Having said that, this is a Private Flying forum - so if you're just doing a PPL, and you come across a cheap Jep, I can't see any reason not to buy it. Probably a good idea to either be confident that you'll be able to learn to use it, or check that your instructor will be able to teach you - remember that your instructor (in the UK) is probably more familiar with a CRP1 - but once you know how to use it, it'll do the same as a CRP1, just as well. And you don't need the same level of accuracy for the PPL exams.)
FFF
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