A Maintenance Sergeant (NCOIC) reports:

A 12 yr Old TEWS Still in Use Today

In his own words- (We cannot disclose his name or location for security reasons)
The fact that the TEWS is self contained is the unit’s strongest selling point. Having to drag the UWS, buckets, hoses, extension cords, a generator, or a power adapter for the aircraft (which units rarely have or the aircraft plug does not work), plus gas path cleaner, and, of course a tool box, out to the aircraft to do an engine flush takes more time than the actual engine flush. The TEWS goes in the back of the gator, gets filled up, rolls out to the aircraft, hooked up (the hoses are attached to, and come with the unit, along with the hot section adapters), started, and then used. The whole set up process takes less than half the time of the UWS. Also, logistically, the TEWS takes up much less space then the UWS, buckets, hoses, adapters, extension cords, generators, and power adapter cords.