Do you turn your phone off regularly? RG was having weird missed-call issues and customer service told us you have to turn it off so the phone can download software updates from the satellite (or something like that). She recommended every night, but we only do ours a couple times a week and don't have any problems anymore.
For the OP, if you just want calls and texting, I have the Samsung Gravity:
http://www.t-mobile.com/shop/phones/...hite-with-Aqua
It's just a plain Jane phone with a full keyboard. Our plan is a family plan, which is probably not what you're looking for, but we get unlimited texting and a ridiculous amount of minutes for about $100 a month for the two of us (but I use my cell as a business phone also).