Which cups/bottles are best from getting 7mo from BF onto FF?

[missbumpy]

I'm thinking of dropping some breast feeds (I've got another thread on the subject) but not sure how to give formula to DD. I've been giving her sips of water in a doidy cup which she really likes but it's pretty messy.
What's the best kind of trainer cup? There seems to be a lot of choice out there. I know some are meant to be worse in terms of causing tooth decay. Any tips please?

it will be the last cup in a very long line that you buy, and probably the cheapest! Seriously, the anyway up cups are quite hard to suck from. We have found the tommee tippee ones you get free from hv great, or the Kids on the go ones with a flip up spout but no valve.