A 250 watt HID is perfect for one or a few small plants. Is it really cheaper to do it with CFL's? Compacts cost money too, especially if not purchased as a multi-pack or something. They also cost money in electricity though and are less efficient than an HID light is. I suppose if there were other extenuating circumstances (extreme heat issues, poor venting ability, limited space, etc.) CFLs would be ideal, otherwise an HID is really the best option.