The pros are you can mount larger diameter tires and the quality of most after market arms are higher than stock. The advantage of having them arched as well (arched or not arched is up to you) is that you increase your horizontal ground clearance. They (straight or arched) do not increase the width of your machine nor do they add any stress to you suspension - unless you add a lift as well. As far as the quality of the BA products, there may be others that come close to the BA quality, but IMO, none are better! Should you add arched to rear as well...? I say yes - doesn't make much sense to have the additional clearance in the front if you don't have it in the rear as well - wherever the front goes, the rear has to follow!! One bright spot is that you only have to replace the lower arms in the rear - you can still use your stock uppers.