Do you want a low tech setup that doesn't require a lot of upkeep, but will limit your plant choices? Would you prefer a high tech tank that requires a fair amount of upkeep and start up expense, but would allow you to grow any plant you want?
Most shop lights are meant to light a room, so there will be a lot of light that isn't directed into the aquarium. I have heard that there are some that are meant for lighting a smaller area, which would work better. You can get a decent amount of light this way, but an aquarium fixture will look better and be more efficient. If the aquarium is going to be a show aquarium then you will probably be happier with an aquarium fixture. Like most things, there are lots of ways you can have a successful aquarium, you just need to find what works for you.