As per most Birkenstock, these are pretty firm and feel uncomfortable when you first get them. I have several pairs of Birkenstocks and this normal as they eventually conform to your particular foot shape. I already knew my shoe size, but if you don't, I'd recommend trying them on in an actual shop first before ordering as they are a close fit and if you have a wider/slender foot, you might feel more comfortable with a different size. I have a few pairs of Gizeh and I love them. I'm lucky enough to not have to wear closed in shoes to work (I'm in Education) and these are perfect for the scorching temperature when I live. As I said, they are uncomfortable to wear to start with, but they wear in after a week or two, depending on how much you wear them and what kind of work you're doing. I'm on my feet all day and I love how these shoes are sturdy and firm, while shaping to my feet enough to be comfortable when wearing them for hours at a time. I wear them for both work and play. They do look at bit chunky so lean more towards the casual side of footwear, but they look smart enough for casual wear and I get comments on them regularly. The white looks great with shorts or slacks and go with most outfits. I also find they support my higher arch. I haven't been disappointed in my Birkenstocks yet and this pair in no different.