David,
I've looked at this several times with a RAP, and it keeps coming back to adding up the extra cost to modify, and what the RPR already has.
Before Magpul released their RAR stock, it was $150-200 to convert the magazine feeding over to AICS type, for the factory stock, more if you wanted a solid stock.
The Magpul stock is about $250, and will meet what you want in capability.
I had one on a SA Remington 700 , and thought the forearm was "soft" - it had a lot of flex that I didn't like for a "tactical" type stock.
The RAR stock is "soft-er", but probably not an issue for 99.9% of what I would actually use it for - I really just wanted to get away from the Ruger magazine, and into a box mag.
I'd like a hunting style rifle, with a detachable box mag, the RPR doesn't quite fit that role for me - YMMV.
In the end, the rifle is still sitting the safe waiting for me to make my mind on how much I want to sink into it.
