Is there anything risky about trading halfs? like, getting vibes or anything like that? thanks. 
Nothing, really. As long as it’s the same yoyo.
ok thanks!
Or the yoyo uses the same axle. Like a Big Ben and a Mini-Motu, like anything Yoyojam axle thing, except the solid spin.
Size doesn’t matter.
I attached a M1 to a genesis. It worked.