Err, not your grandfather's Guess jeans. If you go on Guess.com you'll see they've become quite chic and stylish. Most of their jeans fall in the $100-140 range.
"LOL" to all of that.
They've always been in the same relative price range compared to other brands, and they've never been trendy. If you're going to spend that much money on jeans, and they're NOT trendy, then they better have other benefits for you, like a really, really good fit.
And as me, I'll usually wait for a sale, especially for jeans since they're almost all the same, IMO. I'm only willing to pay a lot for something if I really like it, find it to be unique, and do not believe I'll see them again or have the opportunity to buy it later. If it's something I've seen around, or if I can find something similar and cheaper, then I'd wait.
This is rare, but it happens (e.g. my brown corduroy bell-bottoms with a thick red stripe on each back pocket).

I paid around $120 for those, but they're not trendy, so I haven't seen anything like it elsewhere.