My plates are 5" X 2.5" . I can definitely squish more at a time, just break it down into a few smaller presses just in case I fuck something up. Every once in a while ill over press and blowout a filter bag still when I first sit down to press. I should really hook a gauge up to my press, but just haven't got around to it.
yea i hate blow outs. sunfire reinforces the filter material with a layer of SS mesh around the packet. i haven't got enough hash to have to experiment with that, but it seems like a good idea to prevent blow outs on big hash presses.
when i get a hash blow out i just pack it all back up into a new filter packet and re-squish. not ideal but you can still get very nice oil even after a repress.