i get 6 hours at the highest rate 24mbs on the internal drive. seems i would get 3 hours on a 32gb class 10 card. sony says 2 hours. makes no sense.
anyone recorded on 32 gb sd? how much time are you getting at the highest rate

What does the camera say when switched to the card as target for recording? There may be some "file overhead", but shouldn't be THAT much, 3 hours seems about right for a 32G card.

They may also underestimate to take into account VBR (variable bit rate), high motion frames take closer to the MAX bitrate, thus take more space - if you shoot a lump on a log, it will throttle the bit rate down and take less space...

I recorded a 2.5 hour show last weekend with an XR550. Video came out to 2:58:10 and 27.8GB.