Having owned and driven a few subies I can tell you that the later model gear is extremely asthmatic. I had a GTB manual wagon, it was a slug in standard form, after an AVO interwarmer, AVO dump and cat, HKS catback and a HKS panel filter I managed to extract some beans from it.
Stock standard they are gawd awful. No surprise that the old GTR feels different.
Nice review Bob, good read.