I had to do a bit of prep work, running this on the fly would not be a good idea since they leave a lot of stuff up to the GM (not a bad thing). They also have a lot of options for the players to do different things, which is a pleasant change of pace.
We ran the first part with only 3 people, I should have cut one of the brothers out, but it really wouldn't have mattered due to how it played out. They left one player sleeping and shot first. A shotgun to the face cramped his style quickly leaving them with only 2 players to battle 3 or 4 people. I quickly realized how important modifiers are and how deadly combat can be; Rather not deadly, dangerous. I say that because recovery is possible at the end of combat if you're merely scrapped up or wounded.
Being wounded is a good hampering method. Spreading damage around can make a tough opponent a lot easier. Modifiers are insanely important to combat. A character wearing light armor gets a -1 to damage rolls against him (5+) and an injured opponent has a -1 to hit him (again, 5+), which the character can soak (4+). Normally your odds of hitting and injuring with one die power and one die fighting are 12.5% whereas if you injure the character they're at a 5% chance to wound. Of course with a Fighting of 3 and a Power of 2, a mountain screamer has better odds than that.
So the system is pretty great so far. I think the introduction leaves quite a bit on the table in terms of what they'll offer in the actual book. I really like the setting and can't wait to see some more.
We're only half way, so I'll get some more meat and potatoes of the review out next week.