[bitwize]

I'm familiar with Xlisp, Microsoft Lisp, and PC-Scheme. What I'm not sure about is how performant they were, or whether large systems could be built with them.

[skissane]

> What I'm not sure about is how performant they were,

They were sufficiently performant to be used in anger. I mentioned some of the real world uses

> or whether large systems could be built with them

I mentioned the muMATH computer algebra system, built with muLISP. I think that would count as a large system, at least by the standards of the time.