Charcoal Pan Design ?'s

[golfpro2301]

For those that have insulated vertical smokers I am inquiring about the charcoal pan design. I have always used expanded metal on all sides with angle iron on the edges. I have been seeing a lot that have expanded on bottom and solid on sides with either holes or no holes at all. Anyone prefer one or the other and why or is there solid evidence on one being better than other when it comes to burning the minion method?

 

[bikerchef]

Interesting question. I don't have any evidence. 

Like you I built mine with expanded metal all around assuming I wanted the air and heat flow.