We now have brake pads for the polaris sportsman 850 and 550 xp models in stock. As for using sintered metal pads yes they will wear on your rotors a bit more but is definately a must have for these new atv's out currently. Ebc mainly states this with some of the street motorcycles as you can get some chattering out of sintered metal pad with some of the rotors used on different models but it doesn't effect the atv's. It is a absolute must to replace with sintered pads they will last longer than the typical semi metallic or organic brakes out there.
Complete set front and rear (4 sets) for the 2009 850 xp sportsman $54.95 on
ATV and Motorcycle - brakes or brake pads - Race Driven the 2010 and 2011 use only 3 sets of pads (which didn't make any sense but i guess i do not work for polaris so who knows there reasoning to downgrade to just 3 sets of pads) but the 2010 and 2011 complete front and rear are just $44.95