when you say service, are you referring to network service (phone connection, call quality, data speed etc..) or customer service (advise, trouble shoot, account service)?
network service depends on the location so check with coverage map and ask friends or forum users around your area.
For the customer service quality, I will say it is very subjective depends on one's experience..
in my case... i rarely contact any metro PCS personnel, i buy new phone from internet, activate through automatic system, pay the bills online auto pay, i can do few tricks with the phones myself so no trouble shoot needed.
the only time I need to speak with real person is when i cant activate/switch phone through automatic voice system, in that case i would have to speak with the actual customer service rep and my experiences were all good. they knew my situation and quickly addressed all the issues
i am fine with metro service so far