I have heard good things about the rainbow brand before. I thought about buying one until I saw the price. Two or three vacuum cleaners later I went for the higher priced brand (in my case, the Orek) & I hope it works out better. The Orek comes with the 21 year service contract & I have a store about 15 min from where I live. I also like that it is light weight because it easier to transport up stairs. One thing that I hated with my other vacs is switching the vacuum to the hose attachments. Now I have both the upright and the cannister (but they take up a little more room for storage). I also checked out Dyson (only on the internet). I heard that it was heavy & I heard that the suction was good. The - for me, that was + for others was that it was bagless (I didn't want to clean the cannister).
You've got some good options to choose from,
good luck,
jordan
ETA: Susan I actually replied because of your where does all that dirt go comment. (Boy, did I get sidetracked). I was amazed at the same thing.