I love what I have of their brushes - I have their mini kit and always carry it round with me for touchups and such, it only costs £12 and gives 2 e/s brushes (one normal, one tapered), a mini lipbrush and a small blush brush I mainly use for powder. It's a great little set. And I find their retractable lip brush the handiest thing in the entire world for applying fluidlines.
HOWEVER, if there's one thing it's possibly worth stumping up a few quid /euros more for, its a foundation brush, a good one makes a lot of difference, so I'd try a few and decide which one you like best. IMHO foundation brushes and fluffy blending brushes are the two types of brushes where quality really makes an unbelievable difference to ease of application and final look.
ALSO, be aware that the Body Shop are now owned (for about the past year and a half) by L'Oreal, who allegedly have been caught out still testing on animals (I think I read this on Specktra, do a search), which might put you off. I personally have decided to stop buying anything from Body Shop, though I have to shamefully admit I crumbled when I lost my last mini brushset- I just couldn't find another set of handbag-sized decent brushes, and found I really couldn't do without it. Not proud of it, don't really want to support them, but I really couldn't find another set of brushes I liked even a tiny bit as much unfortunately.
If you're looking for an affordable foundation brush, I notice Marks and Spencers do one (I think from memory there's a branch in Dublin isn't there?), though I've no idea the quality.