I have been told by two different builders their preferences. One said Plywood is best for subflooring in the Kitchen because OSB will swell if wet. Whereas, the other said OSB is better because the Plywood will separate when wet. Which is correct? Thanks for your input.
slynbonar

Sly,
Both builders are correct. Water is the enemy of both materials but Plywood will withstand the damage much better than OSB. Plywood is also stronger and can hold a load better than OSB. The floor material, cabinets, and appliances are alot of weight. I would only go with 3/4 tounge and groove Plywood for my Subfloor.
Hope this helps.

U.S.M.C. Semper Fi !!!