Homesteading, maybe I would take my Texan .457. But only if I had a reasonable belief that electrical power would be available. That could be a generator, solar, home made hydro, or whatever. For "survival" on the other hand, The Texan, and maybe even PCPs in general, would not be my choice. My Texan gives me maybe three shots on a fully 3,600 psi fill. That is not something I want to be doing with a hand pump for that large tank. Honestly, if I had to take one of the two guns I own at this moment, it would be my Gamo Urban, rather than the Texan. My reason would be:
1. The ability to fill the Texan to a proper working pressure would be greatly diminished in a no-power or wilderness situation, while the small PCP can be accomplished repeatedly with a hand pump.
2. Stockpiling pellets/slugs for a smaller PCP would be much easier and less expensive than the 280-300 grain slugs I shoot in the Texan. I could also carry many, many times the amount of ammunition amounting to the same weight.
3. Smaller game is not only more abundant, it is easier to obtain and carry, and it can be eaten before it spoils. In a survival situation, with no electricity, how many people would really be able to cure/jerk a deer for storage until needed.
If actually preparing for survival, I think my personal choice may be a magnum springer or gas ram over a PCP.