I also have a K7 - about 4 yrs now. Very reliable, although only doing light duty.
The reason to purchase it was the K7 up are fully imported from Germany (well, so karcher Cape Town told me).
A thread necro of note here.
My father had a pair - this is back mid 90s.
When they were delivered my mother and I had no idea what was being delivered.
We peered into the truck to see what resembled a pair of coffins (each speaker was in its own crate). The guys battled to carry them inside...