Both look great guys. I am certain that I wouldn't fit in those, though.
I was surprised, when I went to check out a local MB dealership with my wife this afternoon, that I could not comfortably fit into a C300. My hair was brushing against the ceiling. WTH? I'm only 6'2" -- I guess my torso is too tall or I need to shave my head.
I sat in a running C300 with the seat at its lowest setting, but without leaning back gansta style, my hair was touching the ceiling.
So we tried the GLC300 after that. I was able to fit into it just barely so we went for a quick spin. What I noticed the most was the low level of NVH, and fanciness of the infotainment system. The engine wasn't particularly strong and steering lacked feedback, though.
The salesperson had a GLC 43 AMG demo available with $6K off, it was tempting to test drive that one, but we had to leave when we realized that someone was coming to our house to do some work.
It was my first time driving a Benz, and I came away underwhelmed overall. I also didn't like that you have to get Premium Plus package to get heated steering wheel. Audi has it as a standalone option for Q5.