The MPC works just a well with midi keyboards as it does with the pads.
I used a 60 for years, I use a 1000 now for all midi sequencing, computer for recording, I don't midi sync since I have enough inputs for my needs but with my win7 machine and my RME card the midi is actually really soild, but from previous experience I find computers less reliable except in the area of unexpected problems, so I stick to it that way.
I would suggest a 3000 rather than a 60, the 12 bit sound of the 60 is actually higher fidelity than most think, and the limitations of the sampler aren't worth the sound. the 3000 already comes with the good OS, SCSI, FILTERS!! and some midi effects like delay etc. the 60 has no filters, and the 3000 sounds great.
Otherwise I would recomend a 1000 or 2500 with JJ OS, there you get deeper functions with the essence of the MPC still intact, but the 3000 is still a class act and a workhorse with all you should really need except a step sequencer.