After trying this blade for 4 shaves and getting 4 bbs little to no burn i found them on ebay cheeper than all the rest. http://www.ebay.com/itm/180712385882?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649 B
I don't know that much about Personna blades but I thought the medical and lab blades were packaged different than other Personna blades and actually said either medical or lab. But if these are indeed the lab blades, that's a good deal.
If I'm recalling correctly, the Personna lab blades are in the blue wrapper which the ones the OP linked to are. and the Personna medical blades are in a plain white wrapper.