I own a 60mkI and a 3k, owned/sold a 1k, have a couple of friends with 4k's, and a couple with 2.5k's. Have one friend who bought the 5k when it first came out.
I actually liked it much better than I thought I would. I am one of those people who are stuck in the past and love my 60 and 3k (and my SP, fwiw) and still use them. I won't go out and drop 2grand on the 5k myself anytime REAL soon, because it wouldn't really make much sense in my setup; however, if I had to buy a currently shipping MPC tomorrow, the 5k would definitely be the one I would get.
The problems/hangups that I have with it are:
no wordclock
The ADAT individual output channels are tied to the analog output channels (one might incorrectly speculate that you could have up to 20 outputs at once with the right combination of stereo analog, 8 indv. analog, S/PDIF, and 8 ADAT - you cannot, you get the same stereo plus 8 that most all full-size MPC's have.)
You cannot assign entire tracks to go out of an individual output, you must assign individual sounds/pads to individual outputs - which is very odd to me and really screws up the workflow I am used to with my other MPC's.
The things I like about it are:
up-to-date storage media (SCSI gear is starting to get antiquated and difficult to find/deal with.)
current OS development (regardless of your opinion of NuKai - SOMEONE overthere seems to be listening and trying to implement suggestions - hence the 2.0 OS with the keygroup features added.)
Internal hard drive
Things people gripe about that I could care less about
:
24bit samples
only 192MB max memory (my 60 has 1.5MB
Things I wish it had that cannot be added via possible software updates:
No USB host port for plugging a USB/thumbdrive into
Also, since it doesn't have wordclock, an ADAT INPUT might be useful if for no other reason than sync.
Things I am hopeful a future software update might fix/add:
The ability to route whole tracks to individual outputs.
Anywho, given that you can routinely buy these new for under 2 grand and I paid over 3 for my 3000 new, and the 60 was $5000 when new, and the 4k was also well over 3 grand new - I think this is a lot of machine for the money (arguments about swing and feel and groove of the old MPC's not wthstanding)