VBS1 has been around for a couple years, pretty much since around OFP:Resistance was released. The major users of VBS1 have been the USMC, and since I still from time to time get YMs from one of the guys who ran a VBS1 lab, and is currently in a war zone, the dream of a pixellated battlefield is far away.
Recently, the National Guard has a contract, and it looks like the Australian Defense Forces have a program.
The product is primarily sold as a training tool for militaries. The price reflects the developers' view that they will not move many copies, and that the world's militaries have more money to spend on a training tool than private citizens do on a video game. While I haven't actually seen VBS1, all signs point to it being the OFP engine with a few extra scripting commands and some updated models and textures.
OFP/VBS is the only FPS out there to simulate an area of operations larger than a postage stamp. It doesn't suffer from the limitations WW2OL imposed on itself in order to be massively multiplayer. And while the underlying OFP engine is idiosyncratic, it's highly versatile. For example, in OFP, through the use of a couple of models, some self-modifying code, a bunch of hacks and the odd adaptive neural network, we've got a reasonable simulation of all major forms of artillery (mortars, towed, sp, NGF and MLRS) working in-game: the player brings up a Forward Entry Device, specifies the fire mission (e.g., 6 RDS WP/TIME I/E GRID 443002 TOT 1400Z), and the asset in question engages. Heck if someone were to pay me, I could develop a complete "Binocular to Lanyard" field artillery simulation.
Bottom line: you're better off sticking with OFP/Resistance. The last I saw, the only major difference between OFP and VBS is that VBS has some sort of a "mission recorder" -- but how well that's done I don't know.
Of course, some like to brag they spent $500 on a video game.
