We need a bag for every occasion, it’s the law 
@Onanist Andy I have one of those ( the bottom one ) fantastic bag that, not used it for a while tho as I mainly use the Pele case, thought about putting it on here a while back.
Got to agree Rich, it is a great rucksack with ample pockets etc.
I’ll be totally honest with you why I really stopped using it & why I bought the Pele case is ….
If @clinkadink Chris see me with the rucksack I guarantee he’ll have me walking miles so I bought the Pele so when he asked “ have you brought your rucksack rich ? “ No mate we’ll have to stay close today 
Forgot to reply that THIS is what I have been using for quite some time. Lowepro Flipside Trek, it’s the larger BP450 model