I wouldn’t recommend floor polish as a final coat – it is really shiny – more so than a regularly available model gloss coat. At scale, I think it looks like glass rather than polished metal.

I think a floor polish coat is more commonly favoured to accommodate decaling (the super smooth surface significantly reduces the risk of silvering) and protects the paint job when weathering. Once they’re applied, the model is often given a coat of another finish to dull it down as appropriate (though you can mix a matting agent into the polish and use that…).

I only use it on canopies and windows to hide imperfections and give them a glassy shine. I still just use gloss clear coat for decaling and washing. The polish I use is "Long Life" and clears typically Mr Color/Gunze/Tamiya/Humbrol (depending on what I'm applying them over and what I'm gonig to be applying over them.)