Imo rearloaded cabs just can't handle the power coming from the VH4. I tried different rearloaded cabs with my VH4. A pair of custom build 2x12 with Eminence Governors, a Diezel V30 RL and a bunch of Marshalls and whatever cabs that came across when I played gigs with my band. All rearloaded cabs had the same problem. They sounded (depending on the speakers and cab) from OK to great when I stood at max about 2m away from the cab. But the further I moved away the worse it got and when I stood 5m away from the cab all low frequencies were gone and the high mid screaming was nasty.
I talked to Peter Stapfer about this problem and he told me that this is a very common problem with rearloaded cabs because of phasing issues. Espacially with the VH4 because it has extremely strong low mids. That is what gets the cabs into trouble. Not the bass frequencies.
If you use a frontloaded cab were the metal speaker frame is mounted directly to the wood and the cab itself is a lot more stiff because of the overall construction you get a much tighter response and don't loose so many frequencies.
I heard that myself when I was in Dillingen. The frontloaded cab hab so much more punch and was a lot more defined and a lot tigher even when I stood 6 or 7 meters away. We had the VH4's master up to 2/3 to 3/4 and the frontloaded cab still did very good whereas the rearloaded seamed to collapse.
I can only recommend to carefully think about what you want to do with the cab (playing at home, gigging) and what type of music your are going to play. And then trying out as many cabs as possible.
For gigging I personally would never ever use a rearloaded cab again because it will sound different on each spot of the stage and if you have bad luck you get a standing wave somewhere in the crowd or in the singers spot and both won't like you for this.