I bought a 2020 13" Pro (10th Gen i5, 16GB, 1TB SSD) about two weeks ago. It is replacing my 2017 15" Pro. The CPU performance between the two is pretty much identical. I gave up the dedicated GPU in the 15", but I don't really need it... I liked to have it there, but I never really made use of it. I had a Windows BootCamp partition with a bunch of Steam games, but I actually used them about 3 times oner the last 3 years of having that computer. Despite what some say, that Radeon Pro 560 was really pretty decent as far as gaming. That will not be possible with the Iris Plus iGPU, but I am loving the smaller form factor and the fact that the fans are off completely when unplugged and doing basic computing stuff. The fans in the 15" are on always, no matter what.
I obsessed for days over whether or not to upgrade the 10th Gen i5 to the i7 in the new computer, but I decided to save the money because its a 10% more money for like 3-7% more performance. And I really don't think anyone would be able to tell the difference outside of benchmark tests. I could be wrong, but ignorance is bliss. And, as I said, the 10th Gen 28-watt i5 matched the multicore performance of the 7th Gen 45-watt i7 in my 15" and beat it in single core performance. I'm happy with that.
So, in summary, my experience has been overwhelmingly positive. Again, loving the smaller form factor.
