Hello Dwight.
Normally I just enjoy reading these threads and do not interject as there are many here that have far more knowledge than I but just for the sake of conversation here is my observations.
Allow me to lean on your points of importance such as low maintenance and the way you plan to operate the vehicle. Based on your description of events you plan to participate in. All that considered the question from my perspective is why? (Why) pertaining to the need to run a solid roller cam. What advantage does it serve verses it's limitations? Given the operation of your car running a large enough cam to really take advantage of the solid roller doesn't add up. I don't know what size of cam you want to use but given your driving description it should run duration @ .050 intake of 250-260 degrees. With a lift of .600. (That given the heads you are running will be able to take advantage of that size of cam. But that is not your question?) At this size of cam a solid flat tappet verses the power advantage of a solid roller is very slight. And the life cycle of a solid roller will be considerably less and require much more attention to avoid potential failure. Solid rollers with aggressive lobes (which is the only reason to run one) require much more durable ancillary parts that are expensive and will not live all that long. Heavy valve springs, much less valve seat life, rocker arm life, stress to the timing chain, and bronze distributor gear life all will play a factor in the life cycle of your engine and maintenance schedules. So if your motivation for a solid roller cam is extra power you will not have much of a benefit. Especially verses costs and maintenance.
Since your block is designed to run only solid lifters a discussion about hydraulic lifter is mute.
In summary, a solid flat tappet, properly broke in with proper
oil type will give a great power, cost less than 1/2 the parts needed to run a solid roller and live longer. Plus maintenance is considerably less.
One more point so you don't think that I am bias to flat tappets. I like solid rollers and run one in my Cobra but I am willing to live with the results and my cam is huge. I just think, again given your operating environment a solid flat tappet is better.
Regards
Phil