I really cannot see Playstation VR releasing for anything more than $299/£249, because that's the sweet spot and the components to make that headset aren't really that expensive now.
Oculus is a 4K display, PSVR is 1920X1080, both are 120FPS, so the display on PSVR is substantially cheaper to make, the bandwidth for the connections is much less demanding on hardware.
The volume of production is going to be higher on PSVR, because of the install bases involved in each unit.
As for the games, well with VR it's not just about the games, but Sony does have RIGS, which is a PSVR exclusive, plenty of other games are going to be enhanced through VR, like GT: Sport.
I'm sure there are plenty of other games that Sony's studios are working on to support the platform with.
The cost of entry is going to substantially lower on PSVR and Playstation is generally accepted by the masses as THE console, the place to play video games and that console market doesn't consider the PC. Oculus seems to be the more niche device or maybe more for the technical minded area of the market, possibly for more imaging related tasks, than gaming.
I think saying that PSVR will only get three quarters of the market is being way too conservative, I think it's more likely going to be a 90/10 split in favor of Playstation VR. Now how big of an amount of sales that means in general is difficult to say, but I would be shocked if 5% of the PS4 install base won't buy VR, I think PS4 will easily hit 57-60M by the end of 2016, so 2.85M-3M isn't unrealistic, Oculus maybe 285K-300K, though I think even that figure for Oculus is being generous. I could even end being half those numbers for Oculus.
