personally i'm not a fan of waxes that come in a bottle and i'd recommend
collinite 476s not the best wax in the world but probably the best value and gives a nice long lasting finish.
i'd also recommend this clay kit
sonus ultra fine
ash you are aware that you're now on a slippery slope toward becoming a detailing geek, which will consume your weekends and money
me too.. i think though for someone wanting a quicker solution it might be ok... and the megs is only half the price..
have you tried collinite 915... that is pretty groovy stuff too! flippin hard wax though!
that clay kit is a good price and I would say go for that... you'll need a couple of microfibres to go with that too...
i think somewhere there is a polish or wax specifically for black paints?
Just to throw in another option... An alternative to SRP I've been looking at is dodo limeprime. Supposed to be a pure cleanser with a mild polishing action:

i just got some of this but haven't got around to using it yet... have you used it?