it's a short 12 miles as there are many direction changes, but a long 12 miles as there many direction changes. tomorrow will be day 3, so if by "a while" you mean more than 2 days. yes, i've been at it a while. : ) seriously, it's a fun route. good mix of hills, bike path, residential and busy traffic streets. however, my longest single segment is only 1.5 miles.
back on topic, i've read nothing but good things about the banjo. i just haven't pulled the trigger. my safeguard if the hiking pack doesn't work out is that i can use it for hiking or camping which i do on occasion. if the banjo doesn't work, i wouldn't have much use for it.
oh, and unless it made the load completely unmanageable, i would probably pull the frame out for biking.