I got both and both boxes have lot's of character and are very different.
(The mopho is also very different to the evolver)
But it all depends on your needs.
The mopho is no one trick pony but you will need to overdub since it is monophonic. Editing from the panel is bit awkward but the editor software makes it much easier.
The blofeld have a great little interface. I really like the big lcd and editing on it. I'm a fan of combfilters and distortion so when Waldorf came out with this one I just had to get one.
The presets are a bit meh but that is easy to fix.
Make shure you have a pressure sensitive keyboard when testing one though, qute a few patches make use of it. (And tweek when testing!!! it's very easy and makes a huge difference from meh to H*ll Yeah!)
The only problem I have with both is that I keep making so massive sounds that they eat my mix. I just need to practice more sound design (and maybe limit my self).
Summary:
Very cool boxes, Very different flavor, Both very tasty

//s