This is interesting, but the benchmarks suggest that LuaJIT usually does as good, if not better. So there doesn't seem to be much benefit to the static types, at least performance-wise.
Yeah, and the page itself further mentions additional benefits that LuaJIT has that Ravi doesn't, putting LuaJIT even further ahead. As an outsider to Lua, I assumed I was missing additional context (eg. limitations in applicability of LuaJIT maybe?) that necessitates the existence of Ravi.
One reason to use (potentially) Ravi over LuaJIT is that LJ has a 2GB memory limitation.