Bob, agreed. They look nice for sure. However, aren't 3700's supposed to have a flat black air filter cover with built in louvers for more air flow as opposed to (standard) painted covers? I read somewhere on AS that a Tim Allen 3750 recently went for large dollars in nearly mint condition on eBay. I have one but would never believe it's worth large dollars, even though it's nice. Sometimes I think people get a hyper inflated idea of what a saw is really worth. Not throwing stones, but it applies across the saw spectrum and beyond. Hope I'm making sense. Then there's the purchaser. Max.
The 3700's should have the rear vented AF cover. There isn't really much air flow difference between that and the standard cover that's vented through a comb to the carb area in the front of the AF cover
The Craftsman 3700's have the 3400 style cover and I can't see any noticeable difference in performance between the two.
The 3700 cover was also sold separately as a cold weather AF cover.