I use the Delta-V and love it, its strengths and weaknesses have already been covered above.
I know a few people who use the Boundary and seem to like it a lot.
https://www.modulargrid.net/e/schlappi-engineering-boundaryThere is also the Rampage @ 18hp.
https://www.modulargrid.net/e/befaco-rampageYou can also do a "Quasy" 1/2 - Maths using a Contour 1 and the O/A/x2.
https://www.modulargrid.net/e/joranalogue-audio-design-contour-1
https://www.modulargrid.net/e/alm-busy-circuits-alm010-o-a-x2
-- Vow3ll
Looking into all these options, thanks for the info. Contour has such glowing reviews. Would only provide one envelope as Maths has 2 right? Seems hard to beat Maths value wise, but it does use a lot of HP. Still considering Delta-V as well.