I'd love to find an affordable T-50 V1, in fact, I'd go as far as to trade Steve's penis for it too. It seems very well respected (the phones not the penis).
A well designed modern ortho could theoretically make a fantastic phone. The tech is there, it only needs someone to dew eet. Until then, we have limited options, at least the SFI drivers are cheap. I'm half way through modding a K240 fosterfone to fit some of the 120 Ohm SFIs.