Look at enough sandals and you'll see...
Plum lipstick.
No? Okay, just kidding
I have to be honest... my most comfortable sandals, my most loved sandals, my most worn and walked in sandals have been bought at low price points. In fact, as I write my reply, I'm wearing this pair of wedge gladiator sandals I picked up at K-Mart for $10 clearance 5 years ago. Yes, really. Every time I go to toss them, I find myself clinging to them. (They're worn, but I take a black sharpie to the worn spots.) They're not even superior shoe construction. They're just comfie and cute, and I don't think anyone is asking me if I bought them at K-Mart.
My other pair of sandals I purchased three years ago were $40 from Macy's. I wore them until they literally wore out and I had to toss them in the garbage. And last year's pair I acquired from Target. I actually get tons of compliments on them. So I've pulled out Super Glue to repair the strap that finally wore out and came loose.
SO... my feeling is go cheap. They're sandals. I would rather buy a new fun pair every year or two, and use some Super Glue and Sharpies to keep them alive another season. I have never found an expensive pair of shoes I wanted to keep and wear more than a couple years.
Of course, I also grew up wearing jelly sandals as a kid. So, take my thoughts with a grain of beach sand.