I would also go with a gw/x midrange subforum over a naya one because the bant and naya lists are basically the same shell. The only major difference is that one list gets huntmaster/removal and the other gets prime speaker zegana.
Another good store for singles is Thanks For Playing TCG in Ijamsville Maryland. They have a pretty good selection and it is quite reasonably priced. Also some of the owners will just trade the store's cards with you, which is pretty cool if you would rather not spend too much.
I think that they are both pretty similar in terms of how they match-up against the field. Eggs is slightly cheaper though which could be a consideration. Storm is probably also slightly easier to learn to play well, but both require a good deal of practice. It also depends what you expect your local meta to be. Storm is slightly faster so it is a bit better against infect, as well as affinity which can sometimes race eggs but can rarely do so versus storm. Eggs, however, is better against jund due to leyline of sanctity and also probably slightly better against other combos due to most lists running 4 silence, and often 2 of those in the main.
Thanks!