Dangers of using a cell phone as 2-factor auth

Im debating switching from t-mobile to some cheap prepaid provider – im worried about losing my number during the porting process. Is this a legit concern I should have? If something happens to this number, not just during porting, but anytime – then im screwed.

How do you guys feel about this? I was debating using a google voice number as my number for auth – since I have more faith that I wont be locked out of my google account, and I can secure that better than a phone number.

I recently have lost a ton of faith in google (over the past 2-5 years its gotten worse and worse). Is there a google voice alternative that would be suitable for this? And also just in general – is there an alternative to google voice that is worth using?

Found here /// Privacy Galaxy!