The 70$ price tag in itself is also something I have an issue with, but it's with the industry at large.
But I do think the production of this warrants a "full price" label. P3R is not comparable with P3F, P3P, P4G or P5R. The process of its construction is completely different. They're not going into the base P3 project file and changing it, they're building a new P3R project file from scratch. On a technical level, that really isn't any different from making a completely new title.
Will it be any good? Time will tell.