["I want to learn what your smile looks like." What a hell of a sentiment - he almost looks surprised to hear it, those perpetually scrunched brows of his lifting just a little.
It's not a new sentiment, though; just... rare. Impossibly rare. Something he's only heard from one other person - the one who went and disappeared while Chipp was away from Ellipsa.

There Sonic goes again, managing to punch the big guy right in the gut.]

Ahh... J'ai gros coeur.

[It's half muttered to himself, and despite what it means - "I'm gonna cry", more or less - there's little to no change in his tone of voice at all.
As for the weight?
It's cast iron and steel, sure; Sonic's going to be able to lift it just fine, either way. But there's just something... a little heavier in there, too.
Or maybe it's more like something's pulling on it from below - almost as if it wants to be dropped.
Weird!!

Either way, Chipp's crossing his arms on the table again, leaning forward as he watches Sonic heft up his soul just fine.]

Mais, you got some real power to ya. Last time I let someone hold Spin Jockey, they fell right over the moment I stopped holdin' onto it.
You a fighter? Or you just lucky, born strong like that?