That jacket looks like a ‘soft shell’ as opposed to a ‘hard’ shell (a hard shell being fully waterproof and to some degree breathable eg. Goretex jaket, or the normal eVent fabric)
The term softshell covers a wide range of fabrics but essentially they are windproof, more breathable than a hard shell, and water resistant although not waterproof – ie. they’ll hold off drizzle or light rain but when it starts coming sideways the water will get through.
Looking at this though
http://www.outdoorsmagic.com/news/article/mps/uan/4764
suggests that the fabric – eVent windproof not normal eVent waterproof – is still waterproof rather than water resistant like most softshells, but because of the construction the jacket won’t be ie. water will get in through seams if it’s raining hard enough.
Whatever it is, softshells are much better than hardshells most of the time anyway, and Montane make great kit. If you got that for £50 I think you’ve bought well.