All 767s are in fact refitted with 5 rows. Tail number 645 is a new plane just delivered couple months ago.
Seat pitch in J class are 55' in 767, 39 on 737, around 45 for 320, 65 for 747.
Only disadv of sitting in the first row of J class is you might not get your meal choice since they always start from back.
All CP's DC-10s will be phased out soon.
Regards,
Empress