It's honestly going to really depend. I have found this build to be the best late game build. I flip between 1 and 2 a lot lately, but it's mainly team based. I pick Tazer Rounds mainly because late game you can get that extra shot off to get the kill, or your teammates will get it with the extra slowing effects. I don't see anything wrong with using Ambush Snipe, since it makes you more viable early game. Always pick Anti-Armor Shells, since the damage is a bit OP. I prefer Triple Tap personally, but it's going to preference based. I find that I can do more single person damage and depending on who you are up against you can add Fast Reload at level 20 and keep getting kills for days. Lethal Decoy is my preferred choice, I don't really see a benefit from using any other skills. Crippling Shot is what I have found to be the best, I can literally blow up Valla without her knowing what hit her if timed right using this ability. You can use Double Fake if you really want to confuse people, but the 25% extra damage is more useful in my opinion. I have a video below of build in action.
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