Some further info on the tension ability of the Felder FB510. Measured several blades with a Lenox tension meter and determined that the maximum tension that the spring will develop is about 1100 lbs. at full deflection. While I've yet to receive a 1" Resaw King to measure tension directly, my calculations suggest that the FB510's maximum tension with this blade is about 24K psi--somewhat less than ideal. No wonder the Woodmaster CT felt undertensioned--it was only at about 16K psi.
I spoke to Felder service this AM and the claim from one of their senior techs is that they have no data on the spring specs of their band saws and never measure blade tension.
The fit and finish of the FB510 is really very good, but it is not really a dedicated resaw machine unless you want to use a 3/4" RK or a 1/2" carbide blade otherwise.
I hope this information helps others interested in the FB510 as a resaw machine.
Just my $0.02...