hope it's still of use, here are the results on my machine:
when opening big_ugly_patch.pd on pd-0.40.3-extended-20071111 REALTIME: 44.196 REALTIME: 20.901 REALTIME: 20.755 REALTIME: 20.892
on pd-0.40.3-extended-20071011 REALTIME: 37.788 REALTIME: 21.783 REALTIME: 20.706 REALTIME: 21.802
on Pd-0.40.2-extended-2007-03-18 REALTIME: 54.551 REALTIME: 10.755 REALTIME: 10.603 REALTIME: 10.647
and when i did it again after restarting pd REALTIME: 10.918 REALTIME: 10.921 REALTIME: 11.542 REALTIME: 10.855
and when i did it again after restarting the computer REALTIME: 68.318 REALTIME: 10.852 REALTIME: 10.815 REALTIME: 21.318
cheers, robbert