There are like a million of these online HK/china-based sellers - how do you suss out the 'good' and reputable ones from the bad scammers greedy types?
method 1 do exactly what you are doing now research and ask people
method 2 email them and talk to them about stuff see how they communicate
the 2 i've sent stuff back 2 are oz digital online and digital rev both were awesome
oz digital let me send a tamron lens back purely based on the fact i hated it and it was rubbish not that it didnt work or anything, they gave me a credit which i sed towards a canon lens. their return address is in NSW
digital rev i accidentally ordered a nikkor 50mm D lens instead of a G lens they had already shipped it when i realised they called the courier had it returned before it got to me and sent me out the G of course i had to pay the difference but excellent service from either of those 2