J.D.
P.,
You are looking at 3 VERY good school districts, but VERY different structures.
Coppell is a very down home place. The town is very family centric. We don't have as much industry in town as the other two you mentioned. I really love living here. Still, small town feel is not for everyone and the taxes are high.
Frisco is one of my clients. Their schools are limited to a specific number in classes and then they build a new school. Frisco is growing fast. There is tons of shopping and the town seems to have a lot of industry. Industry reduces your taxes, but takes away the home town feel.
West Plano, big city, big school feel. I'm not sure what class sizes are limited to in Plano. This is the least that I know about. I do have friends in the Plano area and they love the school district.
I think all these schools are great academically. You just have to determine where you want to raise your kids and the atmosphere that best suits your family.
Good luck and the best to you! I hope this helps!
Jodi