I know that Denny wil cringe at this, but I made a rye ale from the Craft Beers for Homebrewers book (great book by the way!) using both flaked and rye malt per the recipe...I used a full bag of rice hulls and was glad I did. The mash didn't' stick, so much as the fine gummy flaked rye held back some wort on top of the grain bed when it drained - I got a couple cups more of wort by slicing the top of the grain bed with a few slits and sucking hard to restart the siphon. Worked like a champ, but anticipate this as you run that second/batch sparge through. It fermented like crazy with ice bottles rotated in to cool. The beer literally finished in about five days at 62-64, but I'm going to wait it out before racking. Probably one of the best smelling ales I have ever brewed and I can't wait to taste it!