Welcome!
I'm sure the PNWT would work with the DBV, but there are a LOT of other options. (Many people here who have a PNWT or similar pieces rarely use them. I've had one for 6 months and have used it less than 10 times over that period)
To answer your question - yes the PNWT will leak if you turn it on it's side. There is a splashguard to prevent getting a drink when taking a big rip. But there is nothing to prevent water from running out when laying on it's side.
Before you buy ANY glass, I HIGHLY suggest you check out these two threads. We have scoured the interwebs looking for the best connection directly to China for low priced quality glass. I'm positive you can find something really nice and affordable which you might enjoy more than the PNWT
I would personally suggest you look into the GB-187 sold by Yingmin5, but you'll read about that piece and others' on this thread:
http://fuckcombustion.com/threads/cheap-high-quality-bubbler.5255/page-491
(Read the past 50 pages, there's no use in read the whole thread - it's too big and many old pieces are no longer sold)
There is a new thread which we've tried to compile all information related to reviewing vendors & specific glass models over on this thread:
http://fuckcombustion.com/threads/d...-you-must-post-a-review-see-first-post.15709/
Good luck!
