C3 owner - got the LG SC9S six months ago and the thing that actually got me was the remote. One remote, everything. Volume, input, sound mode, all from the same button i was already pressing. Sounds stupid but i had been living with two remotes for three years and just accepted it as the natural order of things

Most critical factor for your scenario is managing acoustic gain before feedback when dealing with reflective surfaces typical of gymnasium environments. Simple room dividers or temporary acoustic panels dramatically improve microphone performance regardless of equipment quality