Digital BW, The Print

I'm renting time at a lab on an Imacon with flexcolor 4.8.6 (Mac) tomorrow and need help to optimize the settings for scanning black and white negatives (+I'm not too familiar with the program.)

Firstly, is there any benefit to scanning RGB rather than Greyscale?

I understand that if I was converting from a col transparency or col neg to black & white, I'd have the advantage of selecting the best of the three channels for my B&W image. But if the original is a B&W neg, then is there really any advantage? After all there is no col info in the neg to begin with. Or am I mistaken about hoe the software scans and converts to B&W?

I intend to scan at max optical res,16bit, Tif files 
Thanks