I buy wine barrels when I can find them cheap and chunk them up. There are a chit ton of Micro Vintners around here. They usually get used 2 or 3 times before they get decommisioned. There is one guy I bought some from almost cried when I told him I was going to burn them, now I noticed he's selling bags of chips and chunks for $30 on CL! Not much Oak in my area. New barrels cost @ $600!
French Oak that contained Cabernet Sauvignon
Left side - Missouri Oak that held a Cab and a French Oak that held a local Syrah on the Right (used one time)
The only time I could really smell and taste any Wine flavor was a Prime Rib cook done with chunks in my Cookshack Smokette.
Like thirdeye said, the Oak smoke is up front and I sometimes mix it with fruit woods. I've got a lousy sense of smell and absolutely no taste!