To start off with, I don't have experience with the SRX 835, or (knowingly) with any of the SRX stuff. However, I do have experience with the PRX812.
My main opinion is that these are PA speakers. They are designed to provide a large crowd with good quality sound, not necessarily to provide a hi-fi experience inside a home. They will usually have narrower dispersion than home speakers, and may be less refined (ie, more hiss, not as pretty to look at, etc). However, PA speakers like these do tend to have very good dynamic capabilities, especially for a home environment.
Now on to the PRX812: JBL clearly knows how to design a waveguide / horn, and it does show. I have used them in a small room as a temporary monitor, and it performed very well. I also used a pair of them outside, for a small crowd, and they performed very well. The measurements (namely directivity and frequency response) are pretty solid, even comparing to more traditional "home audio" speakers. The main downside is their size, and that they run the 12" woofer up quite high in frequency to match the directivity of the horn, and to enable more output from the tweeter. In my experience, these didn't compromise their sound for PA use, but these technicalities could be an issue for a home environment.
As far as the SRX835P: Personally, I don't think it is ideal for a home hifi setup. Yes, it will get very loud, and if you have a huge room or high SPL demands, then they probably will do well. However, I personally would rather have something like the PRX908P and a sub or two. These have the benefit of being smaller, which usually means wider dispersion, and a lower crossover point compared to the 3-way design.
The other main benefit to the PRX series vs the SRX series for home use is the tweeter used. The PRX908 uses the 2408H-2 compression driver, which is known to perform very well in domestic environments (due to its ring-radiator design, which leads to better high-treble output), whereas the SRX835 uses the 2432H tweeter, which is not as widely loved...
Basically, yeah, PA speakers can work in home environments, but personally I would get one that is better suited for home use. Something like the PRX800 or PRX 900 2-way speakers will have better treble dispersion, and will also be less expensive so you can maybe get a subwoofer as well.