Inflate tool tanking in performance at 25-30k tris?

Hey guys, so I’m following the Piero tutorial from Blender cookie, currently sculpting and this same issue has happened twice now. The first model I was working on started having a huge performance drop at 33k tris, but only when using the inflate tool. It just lags like crazy even with VBOs on. Every other tool works perfectly fine, no lag or anything. As well, when trying to use the smooth tool with shift while the inflate is selected does the same thing. Second model did this at 26k tris.

Running
Blender 2.7a, also attempted on 2.7 and 2.69, didn’t help
Core i5-2400
Nvidia Zotac GTX 560 ti 1GB
Crucial Ballistix DDR3 24gb 1333mhz

Thanks for the help!