I've had a Kav 500i in for repair since August 25th. I received an estimate of 4-6 weeks, and then another two weeks tacked on after I followed up. After twelve weeks and two ignored emails, I finally sent an email pleading for an update (I CC'd every addy I could find on the Krell site). Finally got a response that the unit was "on the bench" and they'd get back to me this week.
Still nothing.
Frankly, the time is not the core issue. My request would be this: I would like periodic updates and more realistic estimates. If you make an estimate and then blow it by 200-300%, that's just bad customer service. If you do that and don't communicate that to the customer, it goes a step beyond "bad".
The service guys at Krell are top notch, and I have a healthy respect for them. But their system is seriously broken and needs to be fixed. Currently, I own four Krell pieces; this experience has me seriously reconsidering the composition of my system.