it seems like it may be a good idea, at times. However, wondering why anyone has done it, reasons, and their results.
I don't like to do it with different brands because i find they always tend to fit badly. However I sometimes mix it up with my kaizens, usually just for some different wood combos
I have never done it because I like my damas how they are, but I think it has to do with how you like to play, what feels best, and most importantly STYLE! My friend Shea did this once, I did not think it looked great because it was turquoise sweets sarados on a krom ken but he did it because his krom spike broke off
I do it to mix woods and improve either lunar balance or looks. If it doesn't fit, I use a weird post-it stack to make the sarado fit. So far, it's worked out well for me, but I make sure that the ken/sword is a lighter wood overall than the sarado. I also make sure that spike is pretty long when I switch.
I do this when I need to. Sometimes it's to get the weight closer to the tama or because I want better lunars/slingers. I once came up upon 2 fresh birch GTs around the same time; one was super light overall and the other was on the heavier side. I switched cups and swords around and had myself a dama that was super good for lunars and one that was better for slingers. I still have the lunar one and it still shlays. I haven't swapped with different woods though. I've always kept the wood types the same
Swapping between brands/models might fit weird, but some mashups prob work great. If a sarado doesn't fit well I usually won't play that dama much.
Made my version of an 'SS1' with Kusa kaizens(sort of). Cherry kaizen spike, T-thorne cups, and ghost silk tama. It was HONED for slings and I played it until the tama had been chipped so badly I couldn't. In my case it worked I guess
I know for a fact that the OG RWB shape sarado and sword can be swapped with any GT shape that isn't a tallboy. Back before Stodd mods were released I put a maple RWB sarado x GT1 maple sword to mimic a poor man's stodd and it slayed hard.
Sometimes the swap fits the ken but doesn't fit the bevel on the tama so wing walker, birds etc are harder.