I'm confused on some of the comparisons.  
1) Download play support: Except some Nintendo games (NSMB, Mario Kart,...) 
Meaning, homebrew can support download play, but "aye-captn" roms cannot?
2) NDS homebrew compatibility:  ...but DLDI fixes it 
I think, but is DLDI a library that is built into the homebrew .nds rom?
I noticed the M3(pre-Simply) is not in the list.  I am familiar with the M3 and it would be nice to know the differences.(eg. can M3 support download play? Is there an issue with DLDI?) I need a Slot-1 vs. Slot-2 comparison chart.
Anyone care to enlighten?