Shoes arrived promptly and feel great.  The last comfortable pair of running shoes I bought were the 1224s.  They simply didn't make my feet hurt.  I run 6-10 miles a week normally.  I also have a pair of the 1225's but, they were extremely stiff and seemed to be trying to mold my feet.  I love the 8512s so far (only ran about 4 miles in them) but, they are very light and comfortable.  I didn't have to wrestle with the laces or even break them in.  I just put them on and started running.  they soles kind of felt like if you took the rubber of a ping pong paddle and layered the bottoms of your feet with it (this is good for me).  I was impressed, i didn't even stretch first...no shin splints, no arch pain, not even calf pains.  In fact the only reason I didn't run longer was because the treadmill actually went into cool down mode for no apparent reason.  I'm looking forward to running outside with these.