I have not try growing Tomatoes in the bag, but earth box. Google EarthBox word and you 'll find lot of peple doing it, beside growing tomatos up-side-down is giving very good result too.

I'm not advocating the growing in a bag solution, but will suggest that you would probably do better with compost or potting soil than top soil. Compost for in the ground, potting soil if you really want to try the bag experiment, because at that point the bag becomes a container, and you'll need the better drainage that potting soil contains. Top soil doesn't generally contain much in the way of nutrients for your plants, so to ammend a hole in the ground that you're planting in, compost would be better.

Best of Luck,
Susan