Sonar v100 studio with fostex d80 and alesis adat 8 channel

hi, i am lookig into getting one of this vintage units with 8 channels.I have also emu 1212m with adat, and was wondering will Ill be able to use them
 
1. if I record with v 100, will fostex d 80 recognize 24 bit, or not., I beleive Fostex is 16 bit. Will that will couse problem? Same with adat?
 
2. or let say, i record directly to fostex, or alesis, how do i avoid unecessary da/ad conversion on both sides.
i am very uninformed about this. pls help