I keep hearing about the return issues with Lumatek ballasts from my local hydro shop- and they carry them! I'd say since they have a vested interest in selling the things, they wouldn't say anything bad about them unless they really did have a lot of problems.
I have yet to buy a ballast or a hood brand new at a retail store, I've bought EVERYTHING I have via Craigslist, or refurbished. For example, there's a grower's consignment shop here in Denver. I'm pretty sure there are other major cities with something similar, or at least the 'used/refurb' shelf at your hydro store. The money I've saved has allowed me to get my buildout done MUCH faster than if I shelled out retail. Yes, I've had the odd failure- a magnetic ballast blew its capacitor, and that same local hydro store had the expertise to fix it within hours. You'll need your local guys, develop a good rapport with two stores if you can.
If you're set on getting a digital ballast, I hear good things about the Solis Tek line. I run standard bulbs with my digital ballasts and I haven't had a problem, yet. If you're worried, SunPulse lighting advertises their bulbs are built to be compatible with digital ballasts.
'Powerbox' is a brand name, and they sell power control equipment. A 'flipbox' is their brand name for a relay box that will 'flip' output power from a ballast between two hoods based on a trigger cord from a timer. There are other, far less expensive flipbox units out there than Powerbox's brand, mostly because they don't spend all the marketing dollars.
This is a good one, less expensive than most, I hear good things about it.
You can safely run one 1000w bulb and magnetic ballast on a standard 15 amp 120v circuit. Don't run anything else on it. And, don't hook your ballast to it through a long extension cord...
I've repurposed my own dryer outlet. The 3 wire plug is 30 amps, you can very safely run 4 x 1000W setups on that, less safely up to 6. The 4 wire plug is generally 40 amp to the dryer, 50 to the stove, you can run more hoods on those of course. Try not to run more than 80% of the rated amps on any given circuit. Whatever you do, if you decide to play electrician, DO NOT just swap out the circuit breaker on the line for one with a higher rating, or you risk turning your wiring into the breaker- and when it gets red hot due to an overload, it WILL burn your fuckin' house down, and maybe you with it!
If you want to save some money, buy and install a gas dryer, then the 30 amp outlet is yours to do whatever you want with, 24/7. Gas is much cheaper to dry your clothes with than electricity. Same goes for gas vs. electric stoves...
When I needed to run 8 x 1000W hoods, I ran a dedicated 6 gauge line from my circuit breaker panel to my Sentinel HGH-8 controller. I used a 50 amp surface mount 4 wire outlet to plug it into, since my controller was used and already had a 4 way pigtail on it. Since the circuit I built (Overbuilt? Maybe, but my irreplacable ass is worth it! Isn't yours?) was then well up to the job of handling 50 amps, I had no qualms about installing a 50 amp breaker in my panel.
Man, power is no place to skimp on safety, even if you do need to save a few bucks. I am not a shy person, and I straight up asked some local firemen if they'd ever been on a call to a house where the grow caused the fire, and they ALL said YES. More than once. "Most" of the victims survived to face charges for growing, code violations, endangering minors, etc... Don't let that poor bastard be you.