Well looking at the book, it says you can shoot both guns as one simple action. This means you can shoot twice from each gun for a total of four shots. The main factor here is that when you fire both weapons you must split your dice pool between the guns. Also remember that one of your guns is an off-hand attack (-2 modifier) unless you have the Ambidextrous quality. So if you have a pool of 8 dice you have to split the 6 dice between the two guns for the first shot. You do not get any bonuses for smart link or laser sight and other ranged modifiers must be applied before you split the pool.
As an example let's say you have the mentioned 8 dice pool. You are carrying 2 Ares Predator IV's, which have no recoil compensation. It includes a smartgun system but you don't get to use it since you're firing both pistols. If you're standing in street in broad daylight old west style you can in theory shoot at your opponent with both guns with 3 dice for each gun. With your second simple action you get -1 recoil for each pistol for a total of -2, which reduces your dice pool to 4. In the same situation you can shoot with 2 dice for each gun. Remember you don't have to split the pool down the middle, in the first simple action you can shoot with 4 dice and 2 dice instead of a 3/3 split if you wanted.
Where it gets interesting is when you factor in ranged modifiers. Say you're in a partially lit alley at night with cover (dumpsters and stuff). Partial light is a -2 modifier and firing from cover is another -2. With the initial pool of 8, you get -2 for off-hand attack, -2 for partial light, and -2 for firing from cover for a total dice pool of 2. This can be split between your two guns for a pool of 1 die each. THEN when you want to fire both guns as your second simple action you get a -1 recoil from both guns for a total of -2, reducing your dice pool to 0. In the same situation if you were to shoot with your dominant hand you'd have a pool of 4 (+2 if you have smartlink since you're only firing one gun, so a pool of 6), then a second shot at -2 which would be a pool of 2 (+2 for smartlink makes 4).
In the alley situation you get to fire both guns a 1 die each, or you can fire a single gun twice at 4 dice then 2 dice. Also don't forget about damage modifiers.
However if you want to min/max a character, you can always get the ambidextrous quality which eliminates the -2 for off hand. Then you can max out your agility (or get cyber arms with agility boosters), and max out your pistols skill. You can also specialize in a particular type of pistol for +2. If I recall correctly at character creation you can have a single attribute at 6, and a single skill at 6 (with all others at 4 or less).
Here's a quick example, obviously there's more options than this but I picked out something pretty basic to have a high dice pool. It was a quick glance over, if anyone notices any errors please let me know and I'll edit it.
Agility 6
Pistols (Predator) 6(+2)
Muscle Replacement (4) +4 Str/Agi, -4 essence
Ambidextrous quality
This gives a dice pool of 18 for a single shot with an Ares Predator. In the old west shoot out you could have a pool of 9/9, then 8/8. In the dark alley scenario you could have a pool of 7/7 then 6/6. But remember the opponent would also have cover which gives him a dodge bonus.
I had a character once that had cyber arms with tweaked out augmentations, then enhanced articulation and super thyroid and all that jazz. Totally min/maxed, but I made it so he would get his hoop handed to him in melee pretty much. It was fun because of all the flair, and I was dropping 4 baddies per pass (remember to add another -2 modifier for attacking more than one opponent in an action). Eventually it got tiresome, all the math each combat round started to get to me.... so I was just shooting each pistol once per round. It made combat last longer for the rest of the group and we ended up having more fun.