
No disrespect to you man, but it sounds like you didn't know what you were buying when you got your MPC. If you didn't want the MPC for it's sequencer then you had no bizznatch buying it. The MPC is the best hardware sequencer on the market, bar-none. Only competition it has in hardware sequencers is it's siblings.
I don't want to come off strong here but the MPC4k is an expensive professional tool. Dropping a couple grand on one, I would hope that you would know what you were getting rather then just hearing your favorite producer used one to make his last album or something. Now whats great about the 4k as opposed to its predecessors is that it also has a full functioning sampler. Now if the only sounds you sample are from your mp-7, and that's all you're doing, you might as well sell that MPC and get back on the MP-7. Personally, along with my 4k, I use a Triton Studio (synth), my turntables with about 10 years of record digging to sample from, multiple fx boards, sometimes I rip DVD's, soft synths, Playstation Games, cd audio, my dog barking, my negighbors f*ck*ing...Whatever I can find.
I hope I didn't offend you with this ramble, I really didn't want to, but what you need to understand is that the plain truth is that you are not at a level (at the moment) where you can understand the benefit of the MPC4k for production because you don't seem to know it's purpose, let alone how to use it. The MPC family is at the center of many excellent producers studios, but if you want a little groove studio in a box, then the mp-7, groovebox, or asr-x is right up your ally....But if you want to take it to the next level then learn that damn thing you got and the only thing that's going to make you want to take the time to read the manual and sit for hours and hours and hours and hours playing with it is the passion to make music. Do you got it?
(off the soap box)