This would put you right around 48". Stock is about 46". You'd be adding 4" overall with the a-arms and then taking away 2" with the wheels. In my opinion, you should run the a-arms that are the widest that you feel comfortable running. I'm assuming you have friends with ATVs, so if that's the case, I'd assume that at least one of them has MX width arms. If you're concerned about tagging trees or rocks or whatever because of the width of your a-arms, then stay with a XC width. Not trying to be a jerk, but this shouldn't really be a question for the forum. This information is purely subjective and is only relevant to the person utilizing it. If you want wide a-arms, buy some. If you want to zip between trees, keep it narrow. This preference will only come from your own personal experience. I personally prefer to keep it as wide as AMA rules allow. The wider the a-arms, the longer the shock can be, thusly giving you potentially more shock travel and potentially more accurate valving. Good luck with your decision.