All Balls sells bearings from a few sources, mostly KML which are in fact made in China. There's nothing inherently bad about anything from China. They make excellent tools and machine parts - also crap tools and machine parts. I believe KML is a decent bearing manufacturer, with good products. If you don't want to deal with local suppliers or learn the bearing sizes you need, use All Balls.
For steering stem tapered roller bearings, the sizes are not stock and you won't find them at a bearing shop. You can special order them but will need to buy a bunch (hundreds?). All Balls has done this, and supplies the spacers and seals needed as well.
For wheel bearings and most engine ball bearings - standard series ball bearings usually stocked at any bearing shop - I buy SKF, NTN, FAG bearings for less than All Balls sells a set for. I don't have anything against KML but given the choice of well renowned brands for less $$ without waiting for them to arrive...