Inflatables like tubes and rafts are fine. As Christina above refers to, however, I would limit them to spring and early summer while the water is higher. Whereas you can always portage easy other times, scraping bottom may be hard on inflatables.While the Buffalo is not necessary a "white water" river, it can get a little rapid at times and may run you aground. Be sure your raft/tube is a sturdy one.
Inflatables are fine. When the river is low bring a repair kit.
I've never seen inflatables on the river. Canoes and kayaks are the only things I've seen.
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