totally - especially given how bandwidth constrained CPUs still are, going wider than 512 doesn't make much sense. 512 itself was a stretch for quite a long time (and all the negative press on the original implementations was a consequence of being not-quite-ready for primetime), but for current hardware I think it's perfect.

But 128bit is just ancient. If you're going to go to significant trouble to rewrite your code in SIMD, you want to at least get a decent perf return on investment!