Only tried the Vive so far. Standard Steam stuff that comes with it is great fun. Simple, well written and plays good.
Not so much with the likes of Project Cars. The frame rate takes a plummet and even on a 1080 - you'll be turning off a lot of the eye candy on order for it play at anywhere near smooth. Looks horribly blocky too - like your face is about two inches from and LED display. That said, I pootled around Oulton Park, staring in appreciation at the door catches, the heater controls and even the stereo on the Evo VI. They were exactly as how I remembered them.
^^^ The truth.
I have a Vive. It has been boxed up in the spare room since I had relatives over at Xmas. Biggest waste of money ever and I'd put it on Ebay if I had an account/reputation etc.
I'd say the only games worth playing on it were actually the games where you stand up and it tracks you fully around the room - and even then I suffer due to a lack of space. The stuff that came with the Vive like the bow and arrow game etc is great but it is just a simple party piece and makes you hot, sweaty and exhausted from having your eyes 5mm from the screens. Brookhaven Experiment is mega scary but very simplistic and short lived. The type of "sit down" games that were initially associated with the Rift (prior to its controllers being released) just play better on a monitor.
The problem with VR is that the resolution is utter sh*te. It sounds good on paper but you have to remember that this resolution is not compressed into a small 16:9 rectangle that takes up only a small part of your field of view. Rather it is spread across a giant sphere filling your entire vision so the pixels are spread so thinly it is more akin to a PS2 game on an old CRT. I'm not talking about "screen door" but literal resolution.
Like in Project Cars you need to use super sampling (which causes my 1080ti to sh*t the bed) just to be able to pick out brake points. I'd rather run it at 4K on my monitor on Ultra than PS2 resolution at medium detail in VR. In old PS2 racing games for example, track side signage like brake markers were deliberately over sized but modern games are designed for 1080p minimum and what you see in the headset looks more like the old SD resolution and it really makes things hard.
Darren is right though that looking at the close up stuff can be impressive. Sitting in a vintage F1 car and having the cockpit sides up by your ear and seeing the wheels and brake disks etc is awesome. Anything more than 5 meters away is garbage though!
TLDR: Avoid VR like the plague. Not even the next generation. Wait for 3rd or 4th. Wireless headsets with 2 x 8K screens. Even 2 x 4K screens would be far too low to get a perceived resolution resembling a 1080p monitor and we ain't even got that far yet. Hell it's not so much the screen technology but the GPU's! The GPU fire power required to get something acceptable to me is ten years off!