[Hectic]

And it also has its other uses. A FTS wont always be as stable, will be able to get hung up on gear and twigs and such. And in most cases will add extra weight.
As for an acog im nit a huge fan of them but I can say on most guns just a red dot is fine. As for zoom i run a 3-9x40 bushnel trophy on my bolt action.
Never sees zoom above 5(for potting ahead) and 3 for shooting in most cases. I havent found one I like yet but ill be getting a short dot type scope for it. Basically a red dot with 1.5-5 or7x zoom. In most cases itll be in red dot mode or 1.5x zoom for shooting.
Zoom isnt all that important for airsoft, esoecially if you are needing to track your shots. Over 2 or 3x you wind up losing the bb (its flight path will leave the fov of the optic) due to the arched trajectory you use at long enough ranges to need zoom to begin with.
As fir sighting in first you shoot down range and get yer hop set well, cant see your black, tan, green etc... bbs? Hang a white sheet or shoot with the sun at your back in morning or evening, the bb will shine, youll see it.
Then you set your sights on the target and clamp down the rifle, shoot, either a spotter or yourself watches ir goes and looks at the target and you adjust the sights and retry untill your in the sights and on target job done, bb color doesnt matter. You can use a bore sighter to get the general area and then fine tune from there.