Is the gas lines that Walmart sale any good?

As long as it says gas line and ethanol rated.

If it's grey in color it is most likely NOT ethanol resistant. Best practice is to go to auto parts house and get fuel line rated for ethanol..

this, I build my own, buy a bulb and get fuel line at parts house (auto line works just fine).

I wouldn't use those volumes sales packaged fuel lines from any store - they are basically the price-point junk. Note that color is NOT the primary indicator of quality. There are junk hoses that are both black and gray!

I'm not familiar that auto parts stores sell fuel line with the proper Coast Guard approval. I'm sure they have ethanol resistant fuel line, but not sure about the certified stuff you SHOULD be using. Note that there are two standards, one for below deck and one for above deck applications. The above deck stuff does not qualify for under deck use, but the below deck rated line can be used anywhere.

"Barrier Lined" Type A1-15 - Fuel Line certified for above/below deck, ethanol resistant, Coast Guard approva; os the A1-15 rating. A1-15 is the thicker stuff you usually see going to the tanks & fittings under the deck of a boat.

"Barrier Lined" Type B1-15 - Fuel Line certified for above deck only, ethanol resistant, Coast Guard approved. This line is slimmer in overall diameter and is what is typically used to run from the primer bulb to the outboard's fuel fitting. When the bulb is under the deck, the rule gets bent a bit to run from that bulb to the outboard.

Trident is a respected supplier of A1-15 and B1-15 fuel line. I got both from Michigan Motors, but they are available from many sources.

Buy the grey EPA approved lines that have BLUE writing. The red and orange lettering will deteriorate.