If you're worried about your amp's health, just be sure they're properly biased. You can use whatever make tubes you want within the approved type of tubes lineup:
EL34/6CA7
5881
6550
KT88/KT100
I don't know exactly what you have but Mesa is now using Sovtek. They're characterized as a very aggressive tube that certainly befits the VH4 for many players, but then it comes mostly from the midrange and that may not be suitable for the scooped shredders or those who want full range clean more like a 6L6 sound without being as (or too) dark.
Check out the following link that I use as a good general guide: http://thetubestore.com/el34review.html
There are many others on the web, but this is a good one IMHO.