Have a couple in the 15x45x60 size range, an old B&L Elite and a newer Nikon, the Nikon has a different power range, 18x48 or so. Then an older 20x60x70 B&L Elite. Usually carry my 60mm B&L Elite cause it is old like me, fairly compact/light, uses a smaller/lighter tripod, and let one of the kids tote the Nikon, which is similarly sized. The 70mm B&L Elite goes to the range and gets used near/in the rig.
The newest addition and one that is quickly becoming my favorite is a Minox 15x56 Bino, I can see detail best with it vs spotting scopes to moderate range, about a mile, it's great for spotting bedded game, stuff in brush/shadows etc. Have used the bino for 3 seasons and prefer it to the spotting scopes most of the time, but it is heavier than the 60mm spotting scopes.