I use horse lead lines as leashes. I much prefer the overall strength and the stronger hardware. A friend loops the other end for me (he has the hardware/materials to make collars, halters, and lead lines).
For everyday wear, I prefer a quality 1 1/2 inch wide collar with a double keep. I also like collars made of seatbelt material, as it helps with collar rub for dogs who work their chains/tie-outs.
I love a good leather collar for "just because". My main issue with leather is that it stretches some, and not enough people pay attention to the ever-changing fit of their dogs' collars. I've seen many dogs slip a leather collar because it was worn everyday and the owner failed to notice the slight stretching.
The Hokey Pokey. That's what it's all about.