this is the Guy that i rode with in Moab after NAHBS, Dave has some really good ideas, if i wanted Titanium this is probably where i'd go. i realise you asked about used/retro stuff but everyone else is linking to new stuff i thought i'd join in.
titanium realistically means a US frame, Dave's prices i think are not particularly high for the off the shelf frames which he does in the larger sizes, ok there would be the usual import costs etc but that's a given these days. having spent some time with him he comes across as a realist regarding all the changes that are going on the bike industry regarding new standards etc, and seems quite a forward thinker.
i was never a fan of litespeed, merlin yes, lynskey are nice but daft(er) money, alot of the others seem unknown for long term quality or are stupidly (but maybe justifyingly) expensive and have long waiting lists.
what i would say is do it, you deserve it, i really enjoyed the process of getting my custom build, it's awesome.
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