Doesn't matter a damn I reckon, do what you feel suits you. All logbooks seem to record the required data, yet many civvie ones include nonsense like T/O and landing times which seems excessively pedantic and unnecessary. Also wraps you up in reams of creative accounting to check your night hours accurate if crosschecked (the old problem of providing too much information)
I kept my Mil logbook with suitable references to NAAB under the double red lines and had no problems whatever through many submissions to the CAA. In fact I get the impression that a mil logbook carries a bit more gravitas than some of the plasticky Civ ones.
All my civ hours are in decimal. All are one line per airframe per day. How the hell could you write a line per sector when pleasure flying or on the rigs in helos, as many do in FW ops, even writing TO and landing times!
My second Mil book came from a surplus store - try a google search on the military form reference, the old one contains 7000+hrs.
It doesn't really seem to matter as long as it is honest.