I have an account with Nindie and the prices are so close to RRP that it is almost impossible to sell them for a profit especially on ebay/amazon/play.
They have a rating system so the more you buy the higher your ranking and therefore you get a discount the higher up you are, but remember you will be dealing with the large highstreet stores buying power!
They also have the allocation system which works with your ranking and how much you buy, so therefore you cant buy the buzz products of the moment which is also a bit annoying!
If I were to do it again, I would start off with some of the dropshippers on this site
Hope that helps a bit!