The difference between the OLD 201 and 251 is that the 201 has a die-cast frame and the 251 featured a frame CNC machined from a solid block of forged aluminum. The 201 was silver anodized, while the 251 was gold.
Borh of those reels have now been replaced - within the new "B" series from Shimano. The 201 lives on as the 201B and now is offered with the forged machined frame (in gold) and the 251 has gone to the great reel drawer in the sky - it is no more.
If you can get an N.O.S. or slightly used 251 for a good price - have no reservations, it is a great reel.
I do believe though that the Luna is at least as good, if not better than the Shimano models - in fact the Luna is more in line with the upmarket and better performing Shimano Calcutta "CTE" models, rather than the standard "B" series Calcuttas. And it is priced accordingly.
For my money, I go Shimano over Diawa every time in this class of reel - because the extrodinary service that Shimano provides is just terrific. They often will send you most small parts for free out of their California office - inclusive of shipping. can't beat that with a stick.
I understand Daiwa is catching on that service sells reels - so they've re-aligned their service model and now are trying to catch up to Shimano's high standards. I hear they hired a new service/parts manager - and that he has a much improved policy towards parts and repairs. O.K., that's certainly a step in the right direction.
Me? I choose to go with the one that had the better service policy from the beginning - and so stick with Shimano.
Ummm, one other thing - you didn't ask about ABU reels - but they have some pretty smokin' reels in that price niche as well (And less too) - and their service, though not in Shimano's league, is still pretty darn good.
Best, Lep
This post edited by Leprechaun 05:55 PM 01/15/2008