The differences aren't really significant unless you're competing, but
technically the CX-5 turbo accelerates and brakes faster than an RDX A-Spec
in all metrics according to Car and Driver instrumented testing.
Although Acura does have some unique platforms and powertrains in their lineup, they're closer to a higher trim level of Honda than a competitor to a true luxury brand.
My biggest reservation with Acura is that their
initial quality has fallen to the bottom of the list next to Chrysler (!) and their
long-term dependability is now below the industry average along with Honda.
I bought a new 2019 Acura RDX Advance that I had to dump at a big loss after 3.5 months because of problems. Unfortunately, the vehicle that replaced it, a 2019 Honda Ridgeline RTL-E was even worse. After a 15-year run with 11, mostly-good Hondas, it became painfully clear that the Honda of today is far removed from the Honda of the 80s and 90s that I grew to love. They've got big problems with both quality and customer service and seem to have realized and admitted to it last year, but I hope it's not too late.
After years of buying and advocating Honda vehicles, Mazdas have replaced the Hondas in my garage.