I've driven my Z for about 8 years in central Florida and I've been through some pretty incredible storms but I always got through it with my Z, the deepest I've been in was just a couple weeks ago it was about 4-5 inches deep I suppose (luckily I left it stock height)... let's just say I didn't stop in it to wait for the light LOL... I will have to say I get a drip of water through the joint between the front part where the T-top meets the A-pillar and the glass in the same spot on both side of the Z very rarely though (only when it's a REALLY heavy storm)
"The dreaded 2nd windshiled wiper swipe when you turn it off its almost like tis showing you that it's boss, and it doesn't have to stop when you tell it to :("-College Boy