I agree, if the budget will stand it a quality steel rod has an indefinite life expectancy - you don't need to think about it again.
Aluminum does last quite a while (20,000 street miles not uncommon), but they should be examined for stretch at regular intervals and discarded before they break the engine.
Aluminum rods also require the engine temp to be higher before serious power, and not everyone is careful to warm up first!
Your head porter should be the consult on cam timing, since it will follow the port efficiency and intake/exhaust bias.
