imo SE rendition of SEM filter is meatier, richer but polite compared to Steiner Parker, which in turn,being a rather different multimode design, finds its excellence in edgier, agressive (thinner?) sound applications, and less controlled/stable resonance.
i wonder how will SE implement the controls for the SEM version of Boomstar, considering the CGI renders show the same front panel for all four versions, and SEM one needs some extra filter controls... for starters, a pot governing mix between LP and HP and resulting notch (band reject) from mixing those two signals. and then a separate switch for BP. that is, if they are going to stay faithful to the original setup.
i agree with DF that SE moog rendition sounds great. it does not sound exactly like minimoog, but i dare say , using SE1X Angel Dust next to my minimoog for few weeks, i actually preferred SE version of transistor ladder for some applications.. its just so juicy and liquid, sometimes even moreso than original.
yet, of all four, im most looking forward to hearing the ARP version of Boomstar... as it quite probably might be something for moi..
the resonance on it is just fantastic if your looking for extra character (beyond moogs sweetness) whilst retaining some tone and warmth.. i can only imagine what will happen when you engage the newly implemented feedback control (a.k.a. headphone trick) and/or analog overdrive on top of all this... mmmm...
303 sounds okay but it has quite a strong competition from existing clones like XoxBox or the upgraded version of it w 2 vcos etc, or Acidlab Bassline3 or Bombass.
PS if you can, please give us some MIDI CC control of important parameters. like minitaur does. that's sorta like best of both worlds, somewhere btwn having, and not having preset memory.