The bazooka works great with the weldless bulkhead spigots for the coolers (whether the 10 gallon round Rubbermaid type or the 20.5 gallon rectangular coolers). The mesh is perfectly sized (you'll still need to vorlauf to set the grain bed "filter") and does not collapse regardless of batch size. Just make sure the SS clamp keeps the braid tight onto the coupler--I've had my braid come off once during stirring my mash (w/o using a SS clamp).
Having used both types of coolers, I strongly recommend the rectangular one over the round one since there's less grain bed compaction regardless of batch size and OG. As a rule (learned from experience), you don't want the height to exceed the width of your grain bed (which, if it occurs, will cause grain bed compaction, loss of spaces between husk material, and will severely limit lautering speed).