Allow me to clarify when I spoke of Boca selling cheap Chinese bearings. These are generic "no name" bearings that Boca sells for model engines. An SKF (or any other well known quality brand of bearing) made in China
will be made to SKF specs and standards therefore providing you with a better bearing.
I have seen the three grades offered by Boca - they'll work but the prices and quality available at local Bearing Supply shops are much better overall. Don't be fooled by Boca's high priced ceramic bearings - the balls may not rust but the cheapo races they use will.