I've had one for a while, originally we used it for our dog. We actually clean up after dog when going on walks... and rather then stink up barrels in garage put bags in diaper genie and it helped a lot. Still, it stinks when you open container... but garage doesn't stink.
Got a second one when daughter was born, use that one upstairs. Never had a problem with smell in her room.
Couple of secrets
1) already mentioned -- roll up diaper and tape it down (before sticking in diaper genie).
2) Use twist after each diaper so it forms a diaper sausage inside.
3) That circle thing on the top lid with the points on it, is special scissors, you put it on the plastic part and spin it around to cut off the sausage when the pail is full.
The thing is NOT intuitive, you really need to read the directions on how to set it up, but, once you understand how it works it works well. It is SIMPLE to use, but you do have a small learning curve. You can buy the refills 4 for the price of 3 at ToysRUs w/ in store coupons every now and then. Otherwise, $4.4x is about the price regularly. The refills seem to last a while, a few months for us, but the pail fills up pretty quickly, usually every day or two have to cut the sausage and throw it out.