When Kemper first gave us the ability to make merged profiles I spent a lot of time making direct, studio and merged profiles and doing A/B comparisons and I was blown away. Ever since then I have only used merged profiles with a real guitar cab, quite honestly because they sound just like my actual amps. I don't understand why merged profiles aren't more popular, they are incredibly easy to make, they just take a little more time but it is so worth it. I suspect this is because 1) it does take a little more time and effort, and 2) because most people use FRFR monitors and merged vs. studio profiles don't make any difference when using a FRFR monitor. But for me, I never play on a stage where my amp can't be heard out front and to me there is a huge difference between FRFR and a real guitar cab on stage in that situation, not to mention the pleasure of having a real guitar cab as a monitor along with the interaction between the guitar and cab (like controlled feedback).
I guess I would just like to encourage those who have the means to try a few merged profiles, if you have a decent solid state power amp and a guitar cab give it a go, you might be surprised how much is sounds like a live amp as opposed to a recorded amp, and in a live situation I would take a live amp over a recorded amp any day.