When I went from a 70's Schwinn Super Sport to a ~88 Trek 560, the difference felt monumental. That was shedding 5+ pounds and introducing a drastic frame geometry change. I'll never forget the feeling when I first pressed the pedals on the Trek - it was like the bike leapt forward.
I expect, that once up to speed, there would be little difference between those two bikes on flat ground. But that feeling was worth a lot, in terms of flat out enjoyment.
No upgrade since then has given me that feeling of a quantum leap. It was purely subjective, since I had no data, but was an unforgettable moment. Whether the OP has anything like that depends on the starting bike.