While it may well be true that mab files remain current longer, the motivating factor for me is that I still find mab by far the EASIEST to use, as I never see any irritating things that I have to somehow overcome before getting started on a download, With mab, without fail, I find that every time the download starts, finishes and opens cleanly and clearly. It's a bonus that it remains current for longer, assuming that's correct.
It's also by far the simplest for the technologically-challenged among us who are not computer fanatics with a need for discovery of complex things. Just as Windows was created to the annoyance of dos lovers to make life simpler for those who just wanted to get on and DO things, mab fulfils the needs of the very basic downloading person, who isn't interested in exploring options any further than is absolutely necessary.
For everyone else who loves a challenge, there's Torrent and other perplexing options to fascinate and delight those of a more technical bent.