I assume that you’re asking about MuSig getting used to combination the contributors’ public keys and an enter that spends immediately utilizing the combination pubkey in a keypath spend. In that case, the on-chain footprint is identical as another P2TR keypath spend.
A P2TR keypath spend is cheaper than any (sensible¹) P2WSH multisig enter, since even a 1-of-1 P2WSH enter is costlier. If the MuSig-aggregated key’s utilized in a scriptpath spend, it relies on the depth of the leaf within the taptree, however for 2-of-2 the depths 0, 1, and a pair of would nonetheless be cheaper. The scriptleaf would solely be costlier beginning at a depth 3.
P2TR and P2WSH outputs each weigh 172 WU (43 vB).
A P2TR keypath enter weighs 230 WU (57.5 vB).
A 2-of-2 P2WSH enter weighs 384 WU (96 vB), from the highest of my head, a 1-of-1 P2WSH enter ought to weigh 277 WU (69.25 vB).
The one output sort that has a smaller on-chain weight throughout the entire lifecycle is P2WPKH. A P2WPKH enter weighs 272 WU (68 vB), a P2WPKH output weighs 124 WU (31 vB) for a complete weight of 396 WU (99 vB). P2TR (keypath) has a complete weight of 402 WU (101.5 vB).
You may additionally discover my weblog publish 2-of-3 inputs utilizing P2TR fascinating, by which I element a number of various constructions and examine their weights.
¹ 0-of-0 and 0-of-1 P2WSH inputs can be cheaper however anyone-can-spend.