Swore off postpaid, but I've jumped ship again :-(

[stasek]

Couple years ago, I switched over to prepaid (TMO), and couldn't be happier. I never thought I would EVER go back to postpaid, but that day has come . Till now, I had 3 lines on prepaid ($50UL everything, $30/1500, $15UL text), so my total bill was always around $100 (with the few minutes my daughter used on the $15 plan). Well, my middle daughter is turning the same age as my oldest one was when she got her phone, and even with the least expensve plan, I would have been paying close to $120/month. Here comes TMO Value plan... With the recent back-to-school promotion, I'm getting 2 UL talk/text/data (2gb shared) + 2 500 min/ul text for $100 + taxes, which should come in at ~$115-$120. So, in the end I'll be paying the same amount, but getting far superior plans all the way around. I still hate the fact that they make you sign a 2 year contract (and check your credit! ), but I've been with tmo for at least 10 years and have been very happy.
If you have more than 2 prepaid lines, you should seriously consider this offer. The $5/add a line promo ends Jan. 2014, so the bill will go up $10 for 7 months.

[JDubTrey]

What exactly is the "back to school promo"? see references to it online but nothing on the actual TMo site. Is is a slight discount on the add a line fee? Are there any links to it on the TMo site?

The reason why I turned down the value plan was 1) the 2 year contract and 2) I assume that value adds on the surcharges and fees that prepaid already includes. Is that correct?

[stasek]

What exactly is the "back to school promo"? see references to it online but nothing on the actual TMo site. Is is a slight discount on the add a line fee? Are there any links to it on the TMo site?

The reason why I turned down the value plan was 1) the 2 year contract and 2) I assume that value adds on the surcharges and fees that prepaid already includes. Is that correct?

That's exactly what you get - $5 off add-a-line till 1/14 (leaving you with ~7 months of paying additional $5/line till the contract is over).
Value plan is like any other postpaid plan, so there are taxes/fees (depending on location) which total probably 10-20% and you don't get subsidized phones. Here's the kicker - if you go to Costco and sign up for Value plan through them, you can get SG S3 for $390 + tax, which is over $200 cheaper than the MSRP. They sell the original SGS for $190, which is still pretty good deal for bnib phone.
If you want to entertain yourself, go over to slickdeals website (I don't know if I can link the site, so you'll have to do some legwork) and under hot deals, search for tmobile. The thread has almost 600 posts and has everything you ever wanted to know about the deal.
With this plan, I think 3 lines is a break-even point. If you need more than that, you'll end up saving money in the long run (and have superior CS - if needed).