My SBC-driving friend is trying to talk my son out of the gear drive for his 350.He thinks the gear drives don't last as well and so on. Big lift, big overlap on a hydraulic cam in his 327. Idles with a serious lope at about 1000 - has a pretty high stall TC (something around 3000 RPM). But the same guy pointed at my heavy valve springs on an FE Ford and told me the prematurely dead timing chain had croaked due to the heavy load of the springs.

My reading tells me the gear drive is more accurate/consistent, lasts at least as well as the chain, and the only downside I've found is that on the FE block Fords, you can't run one with the mechanical fuel pump so it's right out for my Shelby. If I can figure out where to mount the fuel pump in the old F100 (I'd rather not have it in the cab with me), I may use the gear drive on the truck.

My son is in high school, and we're building my Dad's '57 Chev 210 Delray for him. He wants an Acura-killer, and the more hot rod noise the better, so it's going to be the gear drive.

Someone will correct me if I'm wrong - there are a load of smart folks on this forum - but I'd go with the gear drive if you're going to run high RPM, or going to have a lot of valve spring in there. Other than that, it's personal preference. But I'll be interested to see if anyone has any good case for the gear drives being hard on things.