Hmmmm... Tough call. The 80's version needs to be improved upon and those darn legs are the key culprit. Although, like others have said, the Staction really is a decent update to the 80's toy -- with a few additional elements for added flare (i.e. yellow eyes, larger ears, more petruded fins and spikes, and an alien-like 3D head).
This really is a tough call. I do know that I LOVE the Staction and I HATE the 1980's design. I'd say a nice mix, leaning more towards the vintage elements in head proportions (size and shape and ear size) and eyes without the legs fused together.