If you can manage it at all in terms of on-going electrical costs, get a 1000W lamp - 400W really won't give you enough coverage to get a good crop. (The higher wattage lamp units really aren't that much more expensive.) Once you've decided to put the time and energy into growing something, there's really no point in doing by halves...

I use mine for orchids and a few miscellanous houseplants, rather than vegetables, but I'm rather disappointed with my 400W lamp, and my plants need less light than fruiting crops. After everything I'd read and hear from people, I was expecting much greater output than I got. The 400W will, realistically, give you enough light for for fruiting plants over an absolute maximum area 2' x 4'- which really isn't very big.

Also, in the last analsysis, I think people overstate the practical utility of switching to HPS for flowering and fruit set, but you might consider a switchable ballast. You can buy "conversion bulbs" that will operate with a MH ballast but they're less efficient and quite a bit more expensive. Over a few years, you would more than pay for the increased cost of the ballast by being able to use less expensive lamps.

I'd look into a CMH (ceramic metal halide) bulb. It's a white light w/ good properties. W/ the right relector, white painted walls or some type of refective material on the walls, you should be able to do an adequate indoor grow w/ 1 400w bulb. The CMH is only available in a 400w right now. You need only 1 tom plant at a time and a few peppers right...Should do fine. If ya decide to go w/ a 1000w bulb, look at the Hortilux blue MH...You won't need a switchable ballast w/ either bulb. They have plenty of blues and reds........A good reflector will make a huge difference!
Good luck.

I'd like to see some links on well-tested systems if you've got any favorites.

I have some encouraging news on Silvery Fir Tree tomatoes. I've been growing some in three gallon or so pots and the fruit is very good.

The other benefit is that they all get less than 18 inches high above the pots.

I have an overdriven fluoroscent setup, and with a constant canopy height it should be possible.

But I'd look at something like a CMH if I could get a good recommendation on it.

Well Philips and GE make a 400w CMH. You can do a web search for both...I personally like the Philips bulb w/ a vertizontal reflector. I'm able to get the bulb much closer to the plants w/out burn, less wasted light energy.

Good luck.

actually 2 feet by 4 foot is very similar to square foot gardening. you can get away with 4'X4' with a 400mh halide. look into square foot gardening than apply that to your indoor grow under lights.get one that is aircooled with a glass shield and you can have you plants grow right up to the glass.