My boot experience during my ownership is -  
  
Opened first time, did stay up  6 months in summer 
Opened first time, Didn't stay up - Winter 
Removed weight - 
Opened first time, did stay up. - Summer 
Opened first time, didn't stay up - Winter 
Replaced with up-rated SGS struts-  
Didn't open first time, Did stay up 
Penny/rubber washer fix 
Did open, did stay until another winter came 
Adjusted Latch 
Does open, Does stay up   
  
Basically its a balancing act of all the above