If You Could Use Only One Cleaning Solution

I know when on the road if you want to know where the good food is, you look for the restaurants where the truckers eat, and for what work clothes to wear, you look around because the local’s know.

I assume the same applies to carpet cleaning chemicals, solvents, and solutions....ask the pros!

With all your combined years of experience, and knowing that professionals will use whatever cleaning product gets the job done right at the lowest cost and makes their job easiest and fastest with fewest callbacks, you are the people to ask. 

In the past, when I had professionals clean the carpets in rental homes I used to own, I noticed a fresh citrus aroma that I liked very much.

In reading this forum, I often see reference to Hydroxi-Pro Crystal, Procyon, Oxyclean, Citra gel, Citrus Gel, and DFC105, but see no clear choice for any one cleaning solution for general purpose carpet cleaning.  

I just bought a Rug Doctor Wide Track model WT-C2 with its original upholstery/hand tool kit and 60% of the original cleaning chemicals/solutions that came with it (used 5 hours) for 1/3 the price it’s advertised at http://buy.rugdoctor.com/tabid/41/Default.aspx and assume the Rug Doctor retail chemicals/solutions in addition to being cost prohibitive will perform mediocre at best.

Is there one cleaning product (or combination of chemical, solvent, and solution) that you folks agree performs best for all-around general purpose cleaning of the most common carpet types?

Also, any chance I can hook a Rotovac up to my machine?