I have to agree, the synthetic handles are generally much stronger than wood. About the only issue I can see is perhaps eventual effect of sunlight on them. But I live in shady country, so it's probably not an issue.
In hand tools in general, I'm seeing more tools sold that have poor handles. Nothing like putting a little pressure on a new shovel and having it snap because the grain of the handle complete crossed the width of the handle in less than 18 inches. In the past, that sort of junk would have been rejected at the factory.
If memory serves, the issues I've heard about the Gerber/Fiskar axes centered around attachment of the handle to the head. Looking at how the custom aluminum handle above fits to the head and attaches, you must admit these axes and hatchets are a bit different. In general, I hear the steel is good. Since I'm reading reviews online, I can't comment on how the reviewers treated their tools.
Also, one wonders if the product line has gone through changes over the years, as one company bought another and manufacturing was changed/moved.
I think I'll reserve my own opinion until I've tried a few of them. At least one friend has one he likes. I'm not sure I understand the shortest one; I think they call it the Paxe and it doesn't have enough handle for a decent swing.
I guess price isn't really that bad if they're good tools. Also, if you shop around instead of buying at REI you can do OK.
I do like that custom aluminum handle, though. That's a tool you could hang on the side of your Jeep and not worry about sunshine or weather.