I got one of these last month and have been testing it with pleasure. The first thing you think of when you see this very light, "stick" vacuum is that it doesn't look like it will do much of anything and certainly isn't a reason to replace your bigger, corded vacuum. But when you turn it on, two things become very apparent right away:
1. The lithium-ion battery really kicks butt and the brush and suck power of this thing is surprising and impressive. Chalk this up to the fact that lithium-ion technology has really improved in the past few years (note Tesla) and is not what you remember when it sorta worked for ten minutes before starting to fade. This thing will motor for up to an hour on a charge.
2. Not having a cord really IS nice. While I love my bigger canister vacuum, I am constantly pulling the plug out of the wall as I venture too far and I winding the cord up afterwards always makes me strangely pissy and on edge (Someone please research this. Is is a man thing?). Being able to run all over the house or office with the RAM is very gratifying, and it made me think that cords would soon go the way of the dinosaur across the whole vacuum landscape.
Finally, will the RAM replace your corded, canister or upright vacuum? Probably not. Would the RAM make a very welcome addition to your cleaning arsenal and perfect for a lot of every day and spot cleaning? Yes, definitely. While I'll be keeping my beloved Dyson for bi-weekly vacuuming and handling all the stuff I use if for like deep rugs, walls and furniture, etc (especially pets), the RAM is great in our office to quickly do all the hard floors and is perfect at home to quickly clean up the dining room floor after Ursula has eaten and dropped most of her dinner or run around with her friends and left small debris across the apartment.