It really depends on what your needs are. I assume you are scalping, or at the very least, day trading since you need multiple monitors. If you are more laid back like myself, you can use any charting package, as I use no indicators (except volume) and have found less is more.

I used to have a set up that looked more like an air traffic controller than a trading machine. Just be careful, a lot of traders spend a ton of money on useless things. It's a business just like anything else - costs are important as well.