Well....our friend, Military Moron, gives the lengths and weights of those specific lengths of most of the major rail manufacturing companies.
the website is(if you dont have it) Militarymoron.com
Patriot
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Given what I read on MM's site, Troy is competitive in the weight category with KAC. DD definitely wins hands down with respect to weight. I don't know any competitor that even comes close from what I saw.
As there is only a $16 difference between the Troy MRF-C and the DD Omega 7.0, I'd have to say the DD is the hands down best value. There is a $40 difference between the Troy MRF-M and DD Omega 9.0. Here the choice is not quite as clear cut, as it was with the 7.0" versions, because of the larger price difference. I believe the Troy and DD to be of equal quality in manufacture. It's the weight difference which sets the apart from each other.
I am personally still debating on whether I'm going to go with the Troy or DD on my Noveske Recce. I am leaning towards the DD, but I'm not convinced at this point. There are alot of other places that $40 could go. Decisions, decisions ...