Can't speak on the Kleenjet's, but I have used 4 other brands, nothing touched the Sgt Steam overall.
I have one unit that has been on a truck for 6 years, we use the heck out of them - used on probably 2-3 jobs per day. I have only had to replace the unit to head hoses/lines twice on that unit, and had to send it off for repair due to a bad switch once. That original unit has outlasted about 4 other less expensive models we have tried.
The best part about them is the customer service, if and when you have an issue, they are johnny on the spot, and have flat rate pricing that's virtually nothing plus parts, I think it's like $30-60 plus parts.
Service has been the biggest headache for us with some accessories, and them being so good in that regard is why they stick out in my head so much.
http://www.sargentsteam.com/
Email:
info@sgtsteam.com
Call: 800-SGT-STEA(M) [800-748-7832]
Come In: 3131 E 3300 South
Salt Lake City, UT 84109