when I've packed my plates before I will usually do a first layer of clothes, then the plate, then more clothes to account for the slight bend. My concern with the VDH plate or really any plate on the bottom of a checked bag would be that it could get bent fairly easily.
I carry my BP in my carry-on. I don't care about the weight and I wouldn't be worried about it getting bent. My #1 concern is being able to fit as much dive gear as possible into my carry-on, so I have that much less to worry about getting lost or delayed. Normally, the only dive gear I put in a checked bag is my fins. They are too long to fit in a carry-on. If they get lost or delayed, I'll rent some or buy some cheap ones at my destination. I don't put any clothes in my carry-on. If there is room for clothes, that is room I could use for other dive gear. I have been carrying my regs in a separate "personal item" carry-on bag. But, with the VDH plate, I'm hoping I'll be able to fit my single tank reg set in the same carry-on suitcase as my BP/W, wetsuit, etc..
The VDH plate is the best thing I have seen for taking up as little room as possible in a carry-on bag.