I'll be doing gull wing doors on my Z, with the gull wing scallopped into the roof (that's the current plan anyway). Not because I want to... but because I'll have to in order to get in and out of the thing! Between the lowered roof and the door bars of the spaceframe, there isn't much room to get in and out!
As for suicide doors, I would like them on an old Mercury Lead Sled, but I'm not sure about a Z.