I have owned all the vacuum decks in the line with my cosmos three now being in for the 4 upgrade. Yes, Kirk can be slow getting the work out as has been previously mentioned he is still servicing and upgrading the decks that were sold before he acquired the company. Im not normally a patient man but when I factor in the quality of the product the extremely reasonable price and the fact I am dealing with a company with great integrity I dont find the turnaround time to be a big factor. They stand behind their work and make an amazing product that in my opinion is well worth waiting for. As far as the difference between the 3 and the 4 I have heard everything from "night and day" to "cant hear much (any) difference". This is typical of high end audio. I cant hear the benefits of my friends new cables but he can and thats what matters. In James case it sounds like he had a cracked base and waited to long for the repair. Frustrating I know but they didnt rip him off, they performed the service and stood behind the product. If youve got a couple hours I could share some real horror stories about well known "hi end" companys that myself and others were outright screwed by and yet many still sing their praises. I have been an audio hobbiest for 40 yrs and consider the new Sota to be one of the great bargains and most honest people in audio today. A tip to anyone dealing with Sota is to communicate with Donna by e-mail. She will get back to you in a timely fashion and if Kirks input is needed she will see you get a call from him.
Happy listening
Happy listening