Longtime Zamberlan fan - due to perfect fit. Agree w/GregB, REI good for fittings if you're near one. Still wearing old 996 Viol GTX - I take care of the leather and still preferred for hiking uneven terrain. Also less-old pair 167 Mamba-low with BOA closure - makes 'em handy for slip-on. Again, it's the fit. Totally worth it for me. Good luck.
Black ovis is probably the best place to buy boots online. Looks like they have quite a few zamberlan models on their site. They have an excellent return/exchange policy for boots so you can get the right fit. Plus I think there is a rokslide code to save a little money on your order.
And watch for sales at the end of the year from all places listed here. I've bought a lot of Zamberlins marked down. The factory website also has a clearance section.
I look at gohunt for the sizing and it's dead on, then buy from Zamberlanusa.com, currently the boots I am running the Storm and the Saguaro are 30% and 40% off....full price on Black Ovis and GoHunt.