The front ports are usually connected with wires which are polerized.
If the assembly was incorrect and the - and + leads were reversed that was the problem after hooking them up correctly the problem is fixed and the ports are fine. Sadly a unit was lost but hopefully that didn't come out of your pocket-Tell your bro the next time he builds a computer to be more carefull in hooking up the wires to the switches and usb ports.
A add on pci 2.0 usb is the safest way to go its impossible to hook that up wrong. If it was a factory unit the guy on the assembly was hung over or something. The back ports are "hard wired" most of the time to the mother board-very safe, but as you experianced the front ports are hand wired from the mother board and if its done wrong-well, you know. As for the quality of a given piece of electronics-sometimes cheapo is actually better. Ive had expensive equipment broken new in the box and some "cheap" stuff last for 10 years. Its in the cards. Just don't try a trip to mars and put your life on your data unit.
When In Doubt-Format and start over