I've taken a slightly different tack - whilst my military logbooks are still on the shelf as proof, absolutely everything has gone into one big commercial logbook. It has enough columns that I can keep stuff apart - but the world at large doesn't care if your "group A" flying was in a G-reg C172, an N-reg PA28, or a military registered G115 - it's all flying.
To date, this has never given me any problem beyond that of keeping it all reasonably neat and clear.
G