Ron Guth:
In 1910, employees at the Philadelphia Mint produced only 551 Proof Half Dollars, complementing a severely reduced output of only 418,000 circulation strikes. As a result, demand for this date is higher than many of its contemporaries and a small premium is normally attached to this date. Cameo Proofs are rare once again after the previous year in which Cameos became relatively plentiful. Deep Cameo Proofs are either non-existent or extremely rare (PCGS has yet to grade one as of August 2018). The overall quality of this date is pretty good and PR64 seems to be the most plentiful grade and perhaps th best value.