Seconding the vulture speed thing. If you run out of SCBs and expect your shield to drop you should already be running unless the target is already nearly dead.
Even the Python isn't really a match in PvE, since the vulture can keep its guns on target much easier and do stuff like hug Anaconda or Python blindspots, although granted once the Python gets its guns on target they hurt like hell.
In a CZ I make roughly 1.2-1.4mil per hour with a vulture obviously since it's the cheapest I've probably got used to this more than the other ships. The cheap rebuy is nice too, for if you ever mess up.
I'll make about 800k an hour in a CZ with a FDL (you can see the difference the C3 weapons makes right there, but in all fairness the FDL is much better in PvP than PvE. Also honestly I prefer flying the FDL, I just wish it had some C3 weapons.)
In the Python... Well, I can't really tell my profit per hour yet. It's really goddamn expensive to outfit it-- It's hardly A-rank yet.
I'm lacking a decent powerplant (lol, D) and the A-rank distributor (got a B, but I can't find an A one anywhere) and it certainly makes itself felt in my DPS when my Wep capacitor is drained in a few bursts, but while it
does fire it bloody well burns through anaconda shields faster than the capacitor drains.

Dual C2 cannons on the medium hardpoints seem to work insanely well too. First time I've really had any success using cannons as opposed to my preferred multicannons, although it's a real pain in the ass to resupply every half hour.
Edit: Just remember-- The Viper is like an interceptor/pursuit fighter. It's got decent shields for the price, but the real defence is your speed an mobility. The vulture is a heavy fighter. Big guns and strong shields. You lose a lot of speed for it, but you can take on the bigger prey easily.