My concern with them would be vibration resistance and the ability to be mounted in any position (inverted even) externally or internally as the Optimas can. The fact that these can't be mounted inverted is a bit telling, meaning they likely outgas significantly as well which means terminal corrosion along with other related issues. I know that may not be applicable to most of the VX crowd, but I use Optimas on heavy equipment and am also converting my sailboat's auxiliary to electric drive using Blue Tops for the 48V power bank.

Fortunately in using Optimas over the past ten years I've only had one fail prematurely (a Red Top) and actually attribute that to a fault alternator. Always nice to see new technology, but personally I like to see it proliferate into some severe-duty environments for a while before adopting.