I know this topic has been discussed extensively in the past, but I would appreciate further clarity. I have read posts from those who recommend Oneway's 20" Banjo on their PM3520B lathe. However, when I tried to order this banjo today, Oneway responded by saying their 16" Banjo is the correct one for this lathe. I am thus confused and don't want to order the wrong banjo. Help Please, Thanks