I have several friends who have the 15x Leica geovids and they like them very much. They use them for glassing as well, but they also have a set of 80 mm Swaro spotters in a bracket for times when the 15s arent enough power for counting points as is necessary in Pa.
It all depends on where and how you hunt as for what will and wont work well for you.
My personal opinion is that if theres a chance im gonna need more than 15 power, then im not going to be investing in the Geovids or other combination units.
The glasses are being used constantly, whereas the rangefinder is only used occaissionaly if at all on a hunt.
The most important piece of equipment we can own is the glasses for long range hunting. We cant range or shoot that which we havent found first. Mind you my first choice is 15x for general glassing, but then i have the ability to change eyepieces and add power in a few minits if necessary with my twin spotting scopes.
And a regular range finder will work as well as a combination unit for ranging.