I tried Selfish Burger and was quite pleased with it. It's not huge, but it wasn't an expensive meal either. I didn't have to add any ketchup to the burger, it tasted great without it. I think it was fried onions and a relish of some sort.
Their fries are pretty boring but they give you a sauce which I really liked. I couldn't place the flavor; it tastes like it may have shellfish in it.
Their milkshakes are really, really small - I won't bother getting one in future. They do have an interesting looking dessert burger (that I didn't try).
I definitely prefer Burger & Co's burger to Selfish's in terms of taste, but the selfish burger was good regardless. Selfish Burger also has a great exterior facade and real nice atmosphere inside.
I also recently had a Mary's Hamburger burger. It was pretty bad. I honestly don't remember them being so boring but it had been 10 or so years since I had one.