I had a pair of Freestone (non-zip) for 3 years which I really liked; thought they were pretty durable and comfortable although I admit I didn't put a whole lot of miles on them. When they developed a minor leak in one of the feet, I shipped them back to Simms, hoping they'd fix them. Instead I get the word from the service dept. that they're not repairable (really?) but that they'd replace them at no cost (except for $20 shipping) with a new pair of Freestones; thought that was a pretty good deal until I got the new waders, which started to leak in the feet within a few months. Got on the horn to Simms customer service and they told me that they'd had some problems with the low-end products in their line since they outsourced production to China and I could either get another pair of the Freestones (again at no cost except for shipping) or upgrade to a pair of their gortex waders for only $200; the rep told me that since the gore-tex were "Made in the USA" they could guarantee I'd have no problems but if I went with the Freestones, I'd be calling him back within 6 months complaining about the same problems about leaks (no kidding, that's what he said). I got into a discussion with him about what quality control should mean and if Simms is going to put their name on a product it should probably invest a little time in said quality control, but got nothing but the standard company run-around about outsourcing, increasing costs, etc, etc. I replaced the Freestones with another pair of same (didn't have an extra $200 floating around, but just happened to be around Bozeman so I dropped them off in person and saved the shipping cost) in April and yes, they have developed a pinhole leak in the left boot. I'm debating sending them back, since I know where that will lead, or just breaking out the Aquaseal and going after the leak myself, which will probably void the warranty.
Bottom line - I'd be extremely leery about buying any of the low end of their waders since quality control seems to be problematic, at best, and more likely non-existent; if you're going to buy Simms, consider the gore-tex. Sorry for the rant, but just trying to pass on my experience.

Regards,
Scott