Malcom,
I am of the opinion that every time you wet rugs/carpets you can potentially cause problems. Modern rugs and carpets use a lamination process to hold the structure together that doesn't deal well with moisture.
Also, like you pointed, one of the risks is that stains "come back" when the carpet dries. One of the reasons for that (not the only one) is that often when people overwet the carpet, the stains dissolve and reach the padding, so the fibers on the top may look clean, but then as the fibers dry up, the stains wick back up. It's very hard to remove stains from that deep without causing further trouble.
That's one of the reasons I like the "dry" cleaning method. There are plenty of different products out there, the one most people in the vacuum business carry is Host, which also rents out a machine that supposedly is very good. I haven't personally tried them but a lot of people say it's pretty good. (See
http://www.hostdry.com)
Another pretty easy to get product is Capture (see
http://www.captureclean.com), which one can find at HomeDepot, Lowe's etc. I like this product, it cleans well, doesn't have a strong smell, it's relatively inexpensive. Years ago, Sears used to sell a machine that looked vaguely like any bagless vacuum cleaner that could distribute, agitate and later vacuum the Capture powder. I wanted to buy one but never did. Brushing the carpet with a manual brush is a pain in the rear though. But the product works really well with a machine that can brush it for you.
Which brings me to the other suggestions.
Lindhaus (see
http://www.lindhaususa.com/) sells both a dry clean system powder and you can buy either an electric brush or one of their vacuum cleaners that has a built-in dry clean system mode to agitate the powder and then vacuum it up later. I have no experience with their products, but people in Vacuumland seem to like it and there is at least one dealer there who says their products are excellent.
The products I have personal experience with, and recommend, are made by Sebo (see
http://www.sebo.us). The Duo system is quick and easy to use, and very effective. You spread the powder, use the Duo Brush machine, wait 30-60 minutes for the powder to completely dry and then vacuum it up. I really like their duo-P cleaning powder.
The downside of dry cleaning systems is that you absolutely need a very good vacuum cleaner. Not only you usually need to vacuum the carpet before applying the system, you also need a vacuum cleaner that can then remove deeply embedded powder afterwards.
In any case, the price they quoted you for that steam cleaner is absolutely ludicrous if they are not going to give you support that is excellent and it doesn't sound like they will by their response. They probably see themselves as selling a (semi-)professional machine that will be operated by pros and don't want to deal with home owners.
Just for giggles, if you buy *all* the products you see in the Sebo Duo-P page (including the electric brush, the Daisy brush, the hand brush, Clean Box and 5 pound refill), it would cost about $600 depending on what your local dealers and sales taxes can offer. If you add one of their TOL vacuum cleaners, it would get to about $1290 with the X4 Automatic upright or $1520 with their Airbelt D4. They also have less expensive vacuum cleaners (although I have experience with both the X4 and the D4, I like them very much, you may also like the Miele canister or upright machines).
And in any case, if you don't mind a bit of noise, any good old upright vacuum cleaner like a Sanitaire, Royal, Kirby etc will work just as well.
People in the carpet business say that calling a professional steam cleaning crew about once every 18-24 months is still recommended, but for most cleaning you will probably be much happier with the dry systems. Just the fact that you don't have the carpets and rugs wet for hours and that you can even use the room while the powder is drying is worth it from my point of view. Also, now I don't dread having to clean the carpets or procrastinate for months and live with dirty carpets. I can just decide to clean whatever problem stains right now, or do just a room or the entire home with no provocation.
Anyway, my suggestion is that you could buy the starter kit of Capture, try it on your problem spots and/or the high traffic areas (you'll be using a manual brush) and see if you like it. If you like that system, you could rent the Host machine for a day or so and do the whole carpeting. If you think it's something you'll be doing often, you may want to take a look at the Lindhaus or Sebo machines. I think it's way less mess, way easier to store, and the carpets stay cleaner longer because they didn't get wet in the process.
Cheers,
-- Paulo.
Sebo
www.sebo.us
