Is metro pcs a good carrier.?

[LANK.S]

My mom is thinking about switching over to metro pcs because of the smartphones. Me, my mom, and my sister are now with net10 which is great but metro pcs has 4G phones for $29 dollars and that really caught her attention. So metro pcs has plans such as $40 per month, $50 per month, and $60 per month. All plans have there advantges

$40 per month: 500MB of data, 5 hours of music streaming(what is streaming), .5 hours of video streaming, 100 photo uploads, and 10 downloads on apps and games.(unlimited talk and text)

$50 per month: 2.5MB of data, 15 hours of music streaming, .5 hours of video streaming, 300 photo uploads, and 30 downloads on apps and games.(unlimited talk and text)

$60 per month: UNLIMITED EVERYTHING!

Now keep in mind the she's looking for the cheapest and what is good so the $60 per month is out. So its between $40 per month and $50 per month. Oh and what does 500MB of data is speed or how much you can before the end of the month. So also for $40 per month for 3 people is $105 per month, and $50 per month for 3 people is $135. So all I wanted know do they have good service and are they good carrier. Also which plans would be best besides the $60 because we really don't upload too many photos im always on facebook, twitter, and instagram so as my mother and sister.
WHAT WOULD BE GOOD HAVING TROUBLE ON WHICH TO CHOOSE. PLEASE ANSWER AND THANKS.

[Smart]

It has horrible connection at the worst times. It isn't reliable, don't get it