[N8man]

I've not cooked with a flat lid using the multiple hole exhaust design,but I have cooked using:
1. Flat Lid with 2" pipe nipple in bung....
2. Weber Lid
3. Weber Base as Lid

I've not had any real issue with "hot spots" using
any of these lidding methods....

Good Luck with what you choose to do...it'll be fine...