Just got to 1000. Hell and Hell is a joke compared to Dante Must Die and the SSS achievement (which weren't terrible either). Super Dante is totally broken!
I actually only had 4000 kills when I was done tho...
TIP FOR 5000 KILLS:
So I went back to the Raptor News level on Heaven or Hell. In the parts where bob warps you away, enemies infinitely respawn until a certain time has elapsed at about one enemy per second! Just mash shoot!
I got about 80 kills in the first segment and 60 in the second. Even better, if you pause and do "restart from checkpoint" YOUR KILLS CARRY OVER. So just mash shoot until the segment is getting near its end, restart from checkpoint, rinse and repeat. I got a 1000 kills in 15 minutes. This has got to be the best way to do this!