Difference b/w Alpina ST-30 and TR-50 tour boots?

I see two pairs of Alpina touring boots out there that seem darn
similar. Anyone know the differences?

Is there a difference in weight? Model year? I see that the ST-30 is
usually $10 more expensive...

As you may know, I'm always looking for very lightweight supportive
boots suitable for touring. I'm kinda liking the hinged cuff, but I
haven't put in a year with one yet---it does seem to give good extra
support for unstable terrain without adding much weight or impeding
action.

Alpina ST-30:
http://www.backcountry.com/store/ALP...4&mv_pc=r 126

Alpina TR-50: http://www.backcountry.com/store/ALP...ring-Boot.html


--JP
outyourbackdoor.com

PS: I just went to the Alpina homepage and it looks like the ST-30 is
just the newer model of the same boot. I wonder if there are any
meaningful differences in it. Weight? Eh, they're probably the same
boot.