gp 1670f transducer

Does anyone know why the gp1670f supports a ss260 but not a b260 or tm260. This is per Airmar web site, I really hate to put stainless in salt water, but I need the accuracy and power of a 260 ducer. Does the stainless housing transmit differently or what ? What happens if I use a b260 but tell the 1670 it is a ss260?

The GP1670F supports all Furuno 10-pin transducers. It may be an error on the Airmar site.

Thanks so much !