The only thing SMM1 has over 2 are the costumes for Super Mario Bros. 1 game style. If that sounds enticing, I'd say go for it

no man smm1, could be old but it has its essence .

First one is easier to build on.

buy this game it is funny and great

yes, there are several glitches and oversights in the original that you cant do in 2. like layering pipes on top of eachother.