I've had two experiences with Krell service and both have been positive. The first was when I bought a 400xi integrated. Living overseas I asked them to unlock 50Hz and 60Hz and they did it for free before sending my amp to the dealer (SBS, NYC).
My second experience was when my DVD Standard started skipping on DVD's. I bought it used, out of warrany. I inquired about the HDMI upgrade and they said they would change the DVD transport as part of the HDMI upgrade free of charge so I went for it. Sure enough, the unit came back in a new box, with a new transport, and HDMI upgrade. I think it took like 3 weeks for the work to be done.
My second experience was when my DVD Standard started skipping on DVD's. I bought it used, out of warrany. I inquired about the HDMI upgrade and they said they would change the DVD transport as part of the HDMI upgrade free of charge so I went for it. Sure enough, the unit came back in a new box, with a new transport, and HDMI upgrade. I think it took like 3 weeks for the work to be done.