BSD-
The “split ductless” units you describe are in many yeshivas and shuls.
Why don’t you see one there and decide if you like it?
The advice “emlf” gave is spot-on.
You need to know what your requirements are; room size, sun exposure, under a roof, flat roof, etc. – otherwise it’s like buying clothes without knowing the person’s size or even if it’s for a man or a woman.