Personally yes, especially if they might be large. You can also provide the compressed versions, as also @patrick-hoefler suggested, wisely.

If I was you, I won't materialize all files and syntaxes. I would do a single RDF version in N-Triple (very handy to buffer triples line by line...) stored aside your CSV. Then I would let a script (with PHP should not be hard) handle the content negotiation and make the syntactic translation on the fly. Being the input N-Triples you could read a bunch of triples, translate them, spit them out and go ahead until you have finished. It should be efficient.