Absolutely. Win's tank is run solely off 6500K tubes I think, and the plants do brilliantly. Good is a pretty relative term and I use it to describe the growth of plants in my tank.
There are some plants (most of those with colour pigments) that just will not do all that well under 6500K tubes and so it is best to match the plants you intend to grow with the spectrum of light you intend to give them. If you need to do a trade off with the spectrum, and use 6500K lights, you will need to increase the intensity of those lights to deliver an increase in performance, if I can call it that.
KP grows some amazing plants under 14000K - a very unusual colour light as it is usually a trade off for marine keepers between one lower life spectrum and a blue spectrum tube. That's a halide, and so the plants respond to it in a very different way. A 6500K halide will provide amazing results because of it's spot intensity.
If you want green plants, 6500K is fine, but the tank will look odd in my opinion as it's a very crisp white. That's when you mix a warmer spectrum light; but then you lose some of the colour on some fish. If you want to grow a wide variety of plants without having to increase the intensity of the light you provide, go for the powerglos and don't look back.
Many have made the switch and not one person is unhappy about the switch. It's more expensive, but easier and the plants will do better.
As Joshlikesfish said, you don't need fancy lights but then you do somewhat restrict what you can have in your tank and how the plants grow.
Some of us like Simon and Zev have been using 6500K tubes for years and years and have always had good success with them.
Main question is - what are you trying to grow; how fast do you want it to grow, and to what extent are you willing to go to have a planted tank?
Food for thought I hope - There is no single correct way; just different ways each with their pros and cons.