Ron Guth: The 1842-O Half Dime has one of the lower mintages of this series, yet it is still quite affordable in most grades. Most of the other dates in this series have higher surviving populations, so calling this an under-appreciated date is completely appropriate. The finest example is a single PCGS MS66.
The overall strike characteristics are usually strong, and most examples show good detailing of the central devices. The only weakness, if any, usually appears on the details.