Remote play is great. My biggest problem with it though is reliability. The first time I tried it, the Vita couldn't find the PS4 that was literally only 6ft away from it. Took me more than a few tries and switching off other wireless equipment for it to work.
When it did work it was good, though. You can definitely feel the 30fps (I was playing Resogun), and the image quality takes a noticeable hit, and I had some frame skipping as well, but it serves its purpose. And being able to play over the internet when not at home is a fantastic addition. It will probably be great with those time consuming, grinding RPGs. Overall, it is a nice feature, but in my experience it has plenty of room for improvement. Wonder if the software can be update and iron out some of those issues.
The software is definitely updatable in Firmware and will continue to improve alongside Playstation Now. Both solutions are using similar software solutions and the constant development will help improve remote play in FW updates. The Hardware may also be updated in future models - These would not require a change to the external case and a full revision of the hardware, simply an internal change as became popular last Gen (constant 360 motherboard changes)