Forget the the Jigoku SR3-SL (unless it filled ammo for all your weapons, I didn't check to see if it could do this during the beta)
It's all about the
Trax Mallus III with the Red Dot-ORS1, Damage Upgrade (62 Attack), and
Return to Sender, which gave you ammo back for getting kills with it.
But I will say, that interestingly, I had saved a few rifles, and when I started my Hunter, at Level 2 (I think), I couldn't use my Common scout rifle that had 33 Attack, or the one that had 39, but I was actually able to use a Jigoku SR3-SL with the Red Dot-ORS1, Zen Moment (Causing Damage increases Stability), and the Damage Upgrade for 49 Attack.
At level 2!!! (maybe 3).
But seriously, if you run into a Reaver Captian, make sure you switch to the Auto Rifle from the Scout Rifle, and use it in a combo with a Sniper Rifle.
I seriously couldn't keep the enemy's shields down with a scout rifle, they would already be back up after I reloaded.
Primary Weapons:
Scout Rifles: Awesome for PVE/exploring, bad for taking shields down of Yellow Health Bar enemies.
Auto Rifles: Awesome for PVP. I didn't try the one with the massively high rate of fire though, I stuck with the Galahad-B model.
Hand Cannons: NEVER even tried it
Pulse RIfles: Never even tried it
Secondary Weapons:
Sniper Rifles: Awesome for PVE/exploring, good for PVP if you are good at that kind of thing, I'm not...
Fusion Rifles: Essentially a mid-range shotgun, I definitely got some use out of it. Nice in PVE and nice in PVP for campers lol.
Shotguns: Terrible in PVE, great in PVP when you know there is an enemy around the corner. Bad in PVP if that friend has a buddy a few feet back, because the range is extremely limited.
In short, it seemed like each of the weapon types had 2 or 3 stat distributions, meaning that in a way, there isn't just 4 primary weapons, it breaks into 12.
Disregard the damage output on the weapons in these pictures, since they are at different levels, just look at the stat distribution for these.
Trax Mallus III
Rate of Fire: 37.5% (60/160) - 2nd
Impact: 62.5% (100/160) - 2nd
Range: 73.75% (118/160) - 1st
Stability: 68.75% (110/160) - 1st
Reload: 56.25% (90/160) - 3rd
Magazine: 12.5% (20/160) - 3rd
Jigoku SR3-SL
Rate of Fire: 28.125% (45/160) - 3rd
Impact: 78.125% (125/160) - 1st
Range: 71.875% (115/160) - 2nd
Stability: 55% (87.5/160) - 2nd
Reload: 59.375% (95/160) - 2nd
Magazine: 16.25% (26/160) - 1st (tied)
Valka SR3
Rate of Fire: 43.75% (70/160) - 1st
Impact: 50% (80/160) - 3rd
Range: 53.125% (85/160) - 3rd
Stability: 46.875% (75/160) - 3rd
Reload: 70% (112.5/160) - 1st
Magazine: 16.25% (26/160) - 1st (tied)
Percentages measured by pixels in the image, approximated numbers shown in parenthesis.
I still don't understand what "Impact" does or how it is different from the Attack, I think it might have to do with Critical/Precision Hit damage.
In review of the distributions, I find the Valka to be the most interesting and probably what I would choose to take into PVP, especially on the smaller maps like Earth and Venus, but I might choose one of the other options for the Moon.
As for the distributions of the Trax and the Jigoku, I would say that they are both for long range, but it is personal preference. Personally, I like having the higher rate of fire, but at the same time, needing the larger magazine size of the Jigoku could make a difference depending on the conditions.
EDIT: Added a numerical analysis of the Scout Rifle Types