@Rajeev *******
The extension is basically the reason why I started considering going this way. IMO the 20 year one is the best one for "per month" value, but I neither can afford 20 years yet (I mean I could, I just don't want to splurge so much), nor I even know where I'll be in my life in 5 years.
Probably the extension will be priced with the new pricing model, but since the extension will happen in 5 years, plenty of time to plan ahead.