what kind of lighting are u using? Low Stress Training + topping, or Sea Of Green? using soil? A little more details would be helpful, but i'm gonna say that as long as you have either HID lighting or a bunch (~80 watts per square foot) of compact flourescent(no tube fluorescents) go for the good seeds. If you're one to read up a lot and research before you start then you will be fine. Most people dont research and this is why most experienced people will recommend starting with bagseed. I did a lot of research before i started and found this hobby to be especially easy to get good results. However, excellent results will take quite some time for any newcomer.

As well as good lighting, if you're using soil, its very important to get a soil that isn't too hot (too many ferts.). I've always used black gold and it works great. I would also recommend thinking about getting feminized seeds since by the time you determine the sex of your regular seeds and have to kill off your males, you will be disappointed that you only have half the plants you started with. They're not much more expensive. Check out Femaleseeds.nl - Specialising in female seeds for the best price. just my thoughts, and what i experienced when i started. good luck