If it's just snow, Ags will give a bit better traction. However, if ICE becomes part of the equation, neither turfs nor Ags will do the job. At that point you will need chains.
With Ags, you will want chains that are designed for them, not the commpn ladder type. The ladder type will fall down between the lugs and not be as effective as they should be
Here are couple of links to the style you would need with Ags:http://www.tirechainsupply.com/product10.htmlhttp://www.kenjones.com/Scripts/itemdetail.aspx?IK=ATV3&HDR_LINKS=XREF&XGID=CHAIN_ATV_26x12x12&XGDESC
Also, weight is your friend. I would highly recommend that you have the tires filled with Rim Guard.