without the personality included I´m pretty sure I could tell all three apart..
it´s just those lil things you notice but can´t quite describe..

I could say for China her bieyes.. but many huskies have them too..it could be a mix of structure among other things.. she reminds me sooooo much Kavik.. only she´s girl n bieyed.. but they have similar markings and structure

for Ninja..her megaplushiness..lol..she really doesn´t has distinctive markings except a few white patches barely noticeable.. I can´t evewn see them at times.. but I could tell her apart

and as for Roger.. well.. his beady eyes n his bark.. lol.. he does have a white patch on the chest.. a lil black goatie mark on his under chin and a few "ridgeback" hairs on his nose strip.. but even without those I could tell

I think it´s harder with solid colored dogs as black labs (not so much in yellows as you can see slight variations there in color shades n noses) or white hairy poodles.. etc..

that is without personality.. with it .. I think it´d be hard for ANYONE to not know their dogs.. but still there are cases like that.. lol