You care about audio, you want to play online, or you hate waiting 45 minutes for a "quick install."
While saving space is a clear benefit, there are notable disadvantages to using highly compressed files: CPU Overhead ps3+iso+games+highly+compressed+better
Because modern compression algorithms (LZMA, Deflate) work by finding repetition, randomized, pre-compressed data yields diminishing returns. The true "highly compressed" scene for PS3 focuses on (firmware updates, dummy files, unused languages) before applying standard compression. You care about audio, you want to play
While they take up more space, standard ISOs provide a superior experience for several reasons: You care about audio