Mandolin bridge question

[F Murtz]

Not too sure whether to make new questions added to the same post on same instrument or start new one, so I opted for the latter
My commercially made bridge collapsed so I have decided to make one but this poses a question about the compensated bit,the one I had pair forward pair back pair forward pair back but then I found different type with fret metal inlaid where they are stepped differently.
These are the two sorts but they seem to be at odds, can someone explain the difference and which is best?


http://imgur.com/a/G8aZb

[Jim McConkey]

I have never seen the 4-slot version before. Compensation varies by string size, composition, and wrapping, so the "right" compensation will change with every different string set. For my octave mandolins, I lay a piece of old string wire on top of a full-width bridge blank (to create a temporary saddle), and adjust the wire back and forth to get the correct compensation for each string, then mark or measure the position. Repeat for all the strings, and then carve the bridge to match your markings.