The Go and the Rift are targeting pretty different experiences. The Go can only track rotation while the Rift can track position changes as well. This opens up many different actions (e.g. crouching down to pick up a can the road) which boost immersion. If you get a chance to demo a Rift or an HTC Vive, I would highly recommend it.

If your PC has the specs to handle the Rift you're doing yourself a disservice not to buy one at the new reduced price.

I bought one on a whim and expected it to be interesting but I was completely blown away and use it almost every night.

The Go isn't really the same experience because it doesn't track head position or hand position.

$399 is great, but I'm going to have to sell a bunch of stuff to pay for the Go as it is.. cancer med and oncologist visit copays suck :(