There are a lot of cheap PCB manufactures around, but lately I’m hearing about problems with tracks falling off. There is no problem with them when you assemble the PCB, and they work fine, but if you ever need to change a part sometimes traces fall off. I bought some Ebay PCB and etched some boards and I noticed that in some areas tracks would peel off and other areas would be fine. So I got some PCB locally and found tracks don’t fall off very often, if at all. I did a PCB last month were I changed the same resistor on that good PCB maybe 10 times, and all the tracks were fine. If you find a PCB manufacturer with robust PCBs, that is probably bigger news.