they will work very good for vegging, but will be slower for the flowering stage. i know, everyones gonna tell you to get a metal halide or high pressure sodium, but the floros will give you a good crop, just not as quick as expensive lights, plus the budding wont be as intense.
you should be able to get a decent crop none the less

you can put that light as close as possible to your plants, i sugest 2 inches away, maybe 3 inches