I now have both (1 weehugger and 2 flips), my weehugger is the popper version. These are my first wraps and I really like this style of nappy - I have some flip stay dry inserts and some swaddlebees prefolds which I use in both the weehugger and the flip.
The weehugger is neater, it has leg gussets which make the fit more secure and in general they seem slimmer on the baby, however the fabric used for the stay put flaps is cotton (which is backed with some waterproofing) and it does get wet, which means it has to be replaced and washed more often then the flip. It also means that it takes longer to dry after the wash, the flip drys very quickly because it is all made of the same PUL material. The flip is much more straight forward, not so cute and looks like it will last onto a larger baby.
Cost wise at most online stores the flip is £10.95, the weehugger is £13.50. That is before you've bought the inserts.
I'm probably going to buy one more weehugger and two more flips.
Hope that helps