Don't be hesitant to select a plan. as from what I've read, you can change it after activation up to four times per month. Just how that works (i.e., how long you have to wait between changes, or if it can be done from your phone or online, etc.), I'm not sure; but you're not locked in. Hope this helps.
You can change the plan online and its almost instantly. Also you can call the toll free number and do it also. 888-294-6804. I use the Core 99 cents per day its used. If you use the Basic its 25 cents a min. so in 4 min you use one dollar, With Core you pay the 99 cents and for verizon to verizon you can talk as long as you want on that 99 cents. Text package is $10.00 unlimited verizon to verizon and 250 min. for all other carriers.