The DPS and Damage on the Cross Carbine are great but the Stats are really not very good.
The Stats on the Kickback 500 are very good, but the DPS and Damage are not as good as the Crossfire Carbine.
If I had both of these 2 already soulbound to my character, there’s no question; I’d use the agi/crit one. You could test them out on a target dummy or sim.
If I didn’t already have them both soulbound, I wouldn’t even be considering either; I’d probably be going for Mandokir’s Tribute.
As a fresh 85 you want the Kickback 5000 with the Amber Messenger being a close second (Heroic BRC). Until troll heroics the Kickback was pre raid BiS for survival hunter. The DPS difference between Messenger and Kickback isn’t honestly all that large, but it is noticeable enough.
I know what the sims say, but I had a kickback 5000 and tried out a crossfire carbine 2-3 weeks into bwd. was still 349 ilvl if i remember correctly. my dps went up by around 1000. imo, sims are based on a pretty solid execution on rotation. if you’re not that guy, which is pretty likely your first week or two raiding on the hunter, i think you’re going to pull more numbers with the 359 weapon. you’re swapping around 120 agility for 70 weapon dps. on paper weapon dps sims around the same as agility, but my own experience is that weapon dps goes a lot further, and also pulls way, way, way ahead if you are asked to go bm to provide the 3% damage buff for your raid. (missing ret pally)