Anyone know any key differences between the Mammut Samurai's and the Testarossa's beyond color?

I can see the heel is slightly different, as is the shape of the rand material, but everything else seems identical. . or at least very very comparable.

La Sportiva is a SHOE company for a reason. There is also a reason that the Mammut Samurai's is 80 bucks. The thing in this industry you will pay for quality. Any La Sportiva shoe that i have worn ive had no complaints. The testerossa and Shaman are very different. The Shamans have a synthetic upper so you will get no stretch. With the testerossa the whole shoe will stretch. There is nothing like wearing a full leather shoe. If you get them sized right they will perfect conform to your foot. The testerossa's are a softer shoe once you get them broken in. The shamans feel a bit cheap to me. In all reality it depends on what kind of climbing your doing.

I've worn the shaman and I'd say it just feels "stiffer" and twists your foot less. There's also the velcro vs laces difference though.

The fit is very different from the Shaman.

They are basically the exact same shoe, as is the Evolv Shaman. Go with the La Sportiva, I've heard better things about them than the Mammut.