I have an Original Mutron III, and to be honest, yes, it is THAT sound. I haven't heard anything else do it quite like the Mutron, but there are a number of pedals out there than can come pretty close. My personal recommendation would be the Subdecay Prometheus, or Maxon AF-9 as I have experience with them, but I've heard great stuff about the 3Leaf Proton.
I used to own the EHX Q-Tron, and while it is a pretty cool pedal I think there is better out there. The HAZ reissue is a good pedal in it's own right, but to my ears, it just aint a Mutron! I used to have the 00funkmk2 also, and I sold it once I got the Mutron (nothing to do with the Mutron, I just wasn't too keen on the Chunk unit).