I have an unopened Straight Talk kit in front of me. It will purportedly lower my monthly cost from $80 to $50. My AT&T contract is over. My iPhone 4S is a free-agent. Can someone please confirm that under Straight Talk (or most any cheaper pre-paid plain) I won't get the following features: -- MMS (texting with photos, videos) -- Visual Voice Mail What other features will I not have?