It really depends on what you're making you part for. ABS is tougher than PLA so if you plan on beating the part up a bit or if you need weather resistance ABS is your material. I've printed several projects from thingiverse that say ABS and I printed with PLA just fine. The important thing is to do your research and get your settings dialed in for what ever material you're using to print. Also if you're newer to 3d printing pay attention to the state of your printers gears and your nozzle as well as how sturdy your supports are being printed. That will save you from bad and failed prints.