I guess there shouldn't be a problem regarding system stability in general with the addition of this PPA and the installation of this and/or subsequent kernels.

After all, new versions are added up to the list of the already installed kernels, they don't replace the old ones. If a new kernel breaks your system, you can always reboot and select one of the others.

As for the software updates, i also don't think that you're gonna face serious issues.

Most of the kernel development has to do with low-level programming (IRQs, hardware compatibility issues, etc) and minor version upgrades might produce some incompatibilities, but probably won't break your whole system.

As you state in your comment to akbozo, you're willing to test your system and don't have a problem reinstalling if something goes wrong.

So I'd say you go with it.