Totally subjective, but I built a bike pack bike out of a like new '94 Bear valley that was my dads.. I figure the things not the lightest but from what my mates did to them back in the day I reckon its bomb proof, its tange tubed, mine had a Girvin flexstem from new which everything everyone says about ref tightness of steering etc, but it does help with bumps in its new role..!
I had them as a teen had a couple, found the geometry as I recognise now a bit neutral as after various brands I fell for Kona's of the same period,
but touring is not what I was doing then, for the job the Marin is an excellent choice.
I bought another for spares, as its only stx.. so ive a complete bike in the shed that cost me £45 thats mint securing that bikes future for my lifetime.
I ponder what's the spec of both, if similar and you like the specialized , maybe part out the Marin as a spares package, one less bike, no real work..
Ive never had specialized, never fancied one but I think its probably two peas in a pod at that time?