i would upgrade.
does the old door work, certainly.
do you need to upgrade, certainly not.
for me the factors are:
- consistency
- functionality
- appearance
The cajun bandit door fits. it doesn't flex. it's fit won't change unless you REALLY try to change it. It's consistent, and in bbq (especially competitive) - consistency is good.
The OEM door is easy to mis-shape. Bump it. Twist it. Drop it. Now it needs a fixing
The cajun bandit produces a better seal and will maintain it. Winds can pick up over night while you're sleeping, the CB door will maintain a nice seal.
The OEM door will too, as long as you fitted it perfectly before walking away. The CB door also seems to open and close easier and with less fidgeting.
I wish CB would make an improved latch though...
and for appearance, I strongly prefer the stainless steel look over the textured aluminum.