You will definetly want to check out each gym because they are 3 very different coaching styles! Spirit Extreme is also up in that area and a really good small gym program. Depending on what level you are, most of Spirit's teams split practice between Coppell and Arlington, so once a week is a 30 minute drive depending on where you are in relation to the freeway.
Cheer Athletics is in a great location right off the tollway which is 75 in some places. I can get from North Arlington to Plano in 45 minutes using the George Bush Turnpike. You just need a tolltag.
Keller also has United All Stars, they have been hitting the smaller comps this season but are doing well also. No Worlds teams though at United or Spirit Extreme.