I tried our Bissell hot water carpet cleaner using the attachments and it worked well for awhile, but it always left the carpets too wet, and it was hard to get the soap out of them completely.
The Amps is just the amount of electricity the motor requires, so the more amps, the bigger the motor, which should give you more power to run the vacuum that powers the brush attachments.
If it has a number for water lift, that would be good, and the higher the number of water lift, the better it will be at getting all the moisture you put into the carpet out, so it will get more dirt and soap out, leaving you with cleaner, better smelling, better feeling carpets..
Since then, I have learned that the carpet soap you use should be something on the order of
Meguiars low foaming APC+, which works excellent on most stains, etc..
I eventually got tired of dragging this Bissell thing outside, so I ended up getting a real carpet extractor - a Mytee HP60, and this bad boy positively cleans and extracts almost all the moisture out, so drying time is way better and the carpets always come out beautifully.
So, the carpet cleaner will work on some things, as mine did, and if your priorities dont call for more power, hotter water, and 137" of water lift, then you will be fine with what you have; even with all the attachments, it will just not be able to do as good as a full blown extractor - its all up to what you want to do with carpet cleaning, cloth seat cleaning, etc...
Another possibility to think about - a Steamer which can clean all the hard and soft parts including leather really nicely, and not have to rely so much on cleaning solutions, etc.. These are way cheaper than an HP60 Mytee machine and I believe it can also do great work on carpets as well...
Good luck with your search.
Dan F