I've now had a chance to compare the original foam Skywalker ($83) with the new HobbyKing fiberglass Skywalker clone ($97). They are both magificent birds, and it's just incredible how China can produce high-quality fiberglass and ply planes for about the same price as foam these days.
The two have exactly the same dimensions and are otherwise essentially identical in overall shape and size. Although I've only flown the foam one, if the fiberglass and ply one flies the same, you should expect it to be equally smooth and stable in the air, able to handle wind well and carry a huge payload. They're both excellent UAV/FPV airframes and can stay in the air for 40 minutes or more with big enough batteries.
Choosing between them is really a matter of whether you prefer the somewhat more ding-resistant (but harder to repair) fiberglass and ply or whether you prefer foam for its easy-to-hack nature and crash-handling. Normally the choice between fiberglass-and-ply vs. foam would also take into consideration the interior room (fiberglass has much thinner walls so more room inside) but in the case of these two birds, they both have so much room that it's not an issue. You can pack all your electronics, 8,000mah of batteries and your lunch in both, with loads of space to spare.
In the end, I slightly prefer the foam version for a few reasons:
That said, if you care about looks, don't mind the longer build time, and don't crash your planes as much as I do, I think you'd be very happy with the HobbyKing fiberglass version. It really is beautifully made.
Here's some shots of the nose and underwing space: