I have about 100 hours in Bulldog and 5 in Pup.
The Bulldog was built as a military training and counter-insurgency aircraft so it is very strongly built and very spacious inside so as to accommodate fully parachuted and helmeted pilots. Everything is big and solid compared to typical GA civilian aircraft. The downside of all that cockpit space and overbuild is weight and drag, which makes the Bulldog quite slow.
Bulldog is a very nice handling aircraft, very predictable stalls with loads of buffet, and easy basic aerobatics. There is an above average amount of disymetry in aerobatics partly as they had to add a very large ventral strake after testing, so the effect of propwash is quite pronounced, and partly because the metal constant speed prop is heavy. Spins and wingovers to the left are a doddle, but trickier to the right. The reason they had to add the large ventral strakes is because without them it would suddenly tighten the spin after a few turns. Even with the strakes, spins were limited to eight turns. I am not sure that any of the still flying Bulldogs are permitted to do aeros because of the wing spar nearing the end of its useful life.
It was an absolute brick on finals with full flaps - great fun to land as it just did not float about like most GA aircraft. It was more like landing a big plane.
The Pup was like an emasculated version - still quite a sweet handling plane but not the same solidity as the Bulldog.