I went to Above Hide (1 star) in London a few months ago. 3 course lunch for about £50 per person. Food was excellent and the portions were massive. I had the Salmon for a main and in awe at the size of the salmon on the plate. At most fine dining places they give you a sliver of fish but not here.
Worst Michelin star restaurant I've been to was Northcote in Lancashire. Service was mediocre, and portions were tiny. One course was literally a single prawn in a bit of sauce. It was a nice prawn but **** me, a single ***kin prawn... it wasn't even that big.
Best restaurant I've ever been to was Robuchon au Dome at the top of the Grand Lisboa casino in Macau. It had 3 stars and I definitely deserved them, if not more. Service was unparalleled and the food was spectacular. The experience still sticks with me to this day. If you ever find yourself in Asia I would always recommend going even if its out the way. Prices at night are astronomical as it caters to the high rollers in the casino, but if you go for lunch it ridiculously good value. 4 "big" courses with about 10 difference types of bread, appetisers, in-between courses, and petit fours come to about £100p!!!!