I'm not a fan of how they did the Spineclaws, but then again I think the drop rates for everything on the isle are way too low. I've done many a grind in my day. The bigger bag achievement is definitely a head above the worst of them, excepting possibly Insane in the Membrane in its prime. And that's a FoS.
As far as the Spineclaw is specifically concerned, it's not the worst mob in the game. But it is a solid contender for the top ten. It would be nice if the thing was more dangerous, unsoloable in current gear. Then maybe people could be bothered to announce its location and wait for a few others to show up before they murder it.