I'd say this your Premier Fives are probably due a recap just based on age. I can't comment on the teflon caps per se and yes shipping has gotten pretty outrageous. If you don't do it you should really consider finding a local tech to recap your amps.
Factory Teflon Cap upgrade for Conrad Johnson Premier Five
Does anyone have any experience with the factory Teflon Cap upgrade for the Premier Five Monoblock? It is pricey, and shipping those heavy dreadnoughts cross-country with insurance is not cheap either. I don't have anyway to listen to the mod here in CA, as my local CJ dealer has no experience with the mod. On the other hand, it is tempting.