Yes it is. Literally the only flaw I can think of is that due to the GBA sound chip, music is a tad too compressed. Not that noticeable in most of the music, but some, particularly Valley of Bowser, outright sound like farts. That, and the lack of extra content compared to Advance 1, but it still has enough fixes over the original. That, and Super Mario World by itself is beefy enough.