I'm using a Aqua Skinz medium .. I have a huge Connyon ,, I loaded and took out once . too freakin heavy .... If you insist on taking a pile of plugs you can buy a WWII backpack army navy and load it with plano boxes ..
My vehicle plug storage infrastructure is a substantial number of plano3700 boxes stacked in a large plastic tub turned on its side with a couple of small bungees holding them all in place. It allows me to take a lot of plugs to the beach and easily swap boxes from the garage wall unit as need be. while on foot I resort to a commercial small/medium belt bag and only carry maybe 8 plugs some buck tails and a rubber or two. If I need more, I go back to the vehicle. I don't like carrying a bag and putting it on the beach. I like to be on the move and have everything I need on me.
I recently saw a plug storage bag in a catalog (I think a muskie catalog) that was really nice. Huge number of tube storage in a open vertical style. I was thinking about supplementing my boxes with it.
I use a surplus shoudler bag. I think they called it an officer's briefcase. I make one row of 2" dia. PVC cut to 7" and taped together in a row for one half of the bag.(6pcs., there's a canvas divider in it) and the next row is 6" lengths of 2" dia. PVC 6pcs. taped together. It also has a front flap pocket for a few Crippled Herrings ziplock with leaders etc...I've had it for almost 20yrs and
would love to find another one to set up for just jigging. As someone mentioned above, the PVC is for interior vacuum lines. Thin walled and light.