As far as reliability goes, it's reliable in my experience. I have the same setup on my 289, with the spider and the wrench looking links that keep the lifters from turning..we had to drill 2 holes in the valley above the carb (make sure to use magnet when drilling + change oil after) using a cam with about .572 lift, crane roller rockers, stock 302 hydraulic lifters and custom length pushrods (we measured the length with a pencil we cut to size). The setup has never even faultered as far as I can tell, i've put 30k probably on the motor since that install and never had a problem. I was a little scared the setup looked like an accident waiting to happen also but so far no problems, great performance. I can't say I've noticed any valve float up to around 6500rpm. Make sure to use loctite on the spider bolts, and I also went with ARP head studs. The cam was part of a heads / intake / cam upgrade, so I can't say for sure how much HP got from the cam alone but the upgrade was a great success.