Well, there are two problems I can think of with a V30 in a simul/mark series. First, you are talking about loading a (conservatively rated) 75 watt amp with a (generously rated) 60 watt speaker. If you never get your amp above two, you might be safe. I'm quite sure that I've had my amp loud enough to fry a V30 on several occasions. I have frequently used my MK IV as my sole back-line on outdoor stages at very high levels. I pretty sure a V30 would not have survived that abuse.
The second problem is that, in my experience, V30s don't sound quite right in open-back cabinets.
But, if you've got one laying around, what have you got to loose?
