Side Zoom doesn't exist, or at least not that I have ever seen. Side focus makes more sense, thus the non existence... I reckon. I like me a Bugbuster though, regardless of what others think!
those are nice pesting scopes for sure .. but yes, side zoom is the rare animal i was wondering about .. a quick zoom on a light pesting rig is exactly what i want, dont got time to mess with focus or grab the back of the scope ...
Never seen a side zoom scope, you got a link? Sounds interesting.
as far as quick target acquisition the best bet is wide angle prism or LPVO scope with fixed parallax. Or you can set the parallax at the far end of your shooting distance and turn down magnification down low so you can see up close and still can zoom in half way even up close. Think of them as adjustable/custom fixed parallax scope but field of view isn’t as wide.