Ok,... I'll bite on that one!!
I recommended the 424mk2 for the reason that it's a few years older than the MK3, and therefore, you're gonna pay much less in bid price, vs. the MK3,... which often bids up near new/retail prices still, by virtue of it still being the newest/latest model available.
On features alone, the 424mkIII has the 424mkII topped. If you already have the 424mkIII, then don't waste a moment worrying about what you might have missed in the 424mkII. The answer is: nothing.
If you're on an MF-p01 budget, your next step up [IMO] is the 424mkII, based on real street value, current bid prices. If you have more cash to kick in, of course going for the 424mkIII makes sense.
If you really want the cream of the 4-track Portastudio crop, as NEW equipment available in stores as RETAIL,... then the 424mkIII is still available for a reasonable $300, BRAND NEW, and I'd say that's your best value in cassette 4-tracks in BRAND NEW equipment.
I hope this post puts my thoughts in perspective. As always, YMMV.
