I have not experienced the Opus 7 in person yet, but from what I have heard, for the price, you cant go wrong with it. Johannus is really setting itself in the world of digital organs of building high quality, and fine sounding instruments at a very affordable price.
My personal favorite modern organ company besides Allen organs is hands down Johannus. They are just fantastic sounding organs. If you like that european sound that is!
As for 30 vs 32. Personally playing a 30 note pedalboard has always been far more comfortable than 32. Dont know the spacing difference, if there is one.
Its not like you will use the top 2 notes in standard classical organ repertoire often, so you aren't really loosing much with going with a 30 note pedalboard.
1905 Story and Clark Art Case
--NEW!--- 1964ish Conn 640 vacuum tube theatre organ! (with leslie!)
Grandmas- New Hyundai petite baby grand
Church (the organ I practice on)-
1998 Bedient (Built about 45 minutes from me!) 2m/pedal 24 rank Cavaille-Coll style pipe organ