I don't think it should be an issue, but idk for sure -- I used a bulk find/replace when I switched, so the switch for me was find/replace, upload, up-and-running -- Personally, in your situation I'd throw up a test subdomain and check it out to see what happened if I used both driver types in the file. Then there's no question or possible "goofy glitches" between different hosts and server settings.
Not to the whole site...I was just going to do a private test directory. As it is...I ended up just putting the site in maintenance mode and did the conversion in about a minute. Now will go back and do tweaks for better performance, etc.