Hi Mike,
Steam cleaners are a bit of a nightmare (in my experience).
Karcher or Kranzle are generally good bits of kit - and theres is the added bonus that they are relatively easy to fix, with all parts readily available.
If you want something that is no hassle - get either of the above. But (and its a big but), the larger you go with the machine, the more times it is likely go wrong.
What were you thinking of using it for?
Luke