Hello 
I want to ask if someone have an experience with trying to put 0.8mm pitch BGA on pcb from any cheap Chinese manufacturer with 6/6 mil routes and 0.3mm drill 
I can easy route 1mm pitch BGA on this specs, but as all RAM chips are at 0.8mm pitch I cant route track between pads and via will too big 
Is here any other solution than to put via in pad and try luck ?
Any real experience or advice than use better manufacturing process ?