I find full fat coffee very strong tasting after drinking decaff for the past year. I used to /LOVE/ coffee, the stronger the better (I think I became addicted to it) and would often buy a large Costa coffee on the way to work.
I have the occasional caffeinated coffee now and never notice a caffeine hit from it. Neither did I before, that I was aware of. I did have a big lift (for an hour or so) from a Pro Plus years ago, before I started drinking coffee much, but the last time I had one it didn't seem to have any affect.