Some people seem to love the system, but it never worked out for my group. You see when you roll, your rolling against a target number. For every 4 point over that you get what's called a "raise" it's sort of like a success level. Where my group ran into trouble was in combat. Especially ranged combat. The target number is 4 on ranged attacks, modified by range [short +0, Medium -2, Long -4 to roll]. Most combats took part at short range, so no modifier for rnage. It was not unusual for my players to roll in the teens and twenties on their rolls. Well that meant with a roll of say 12 they hit with 2 raises, wich added +2 damage per raise [+4 total]. Then they would roll damage [2d6+1 AP1 {ignores 1 pt of armor} for a Colt Peacemaker]. On damage it was not uncommon for them to roll in the twenties because of the exploding dice. Lets say they rolled a 18 on their damage, +4 for the raises on the to hit roll, so 22 damage total. A Toughness [kinda like DR, you have to roll above toughness to do damage] of 7 or 8 is quite high. So 22 - 8 = 14, they beat the targets Toughness by 14. Well divide that by 4 and you get 3 raises worth of damage, that's enough to take a character from healthy to almost dead. There are ways to reduce that, but like I said my group had a way of rolling high. it was not uncommon for them to get 4 or 5 raises on damage.
Which means that they killed damn near anything I threw at them. This lead to a false sense of power and invincibility. The first time an enemy did as well on a roll as they did they were shocked and cried foul.
EDIT: I was using the first printing, the second printing added in a lot erranta and changed some of the rules, so it my have fixed the problem I experienced in play.