I bought a Karcher at Costco that failed real early. Costco connected me to Karcher, who sent me a new machine and authorized return of the failed unit. The replacement units failed early or wouldn't work out of the box. I kept after them and the 6th washer that they sent me worked great and has continued working for the last 6-7 years.
Apparently their quality control at that time was non-existant - and I can't tell you how good their quality is at the present time. I know that the cheapy elelctrics aren't all that reliable.
My brother gave up on his electric and bought a higher pressure unit with a Honda engine that does work great.