I lurked for about a month on several forums after getting DSs for the whole family. It kinda reminds me of the "Ford vs. Chevy vs. Dodge" days from high school 30 years ago. I read everything i could find on every card i could find, in the end, i threw most of it out the window.
I am now the proud owner of:
R4-III - apparently a FAKE r4... but you know what, it works GREAT for our 3yo and supports SDHC. I simply set the border for the highlight to black in the menu and used black images for the Media and Slot-2 options... now he turns it on, sees the joystick icon, picks his game from the list by it's icon and leaves me the hell alone about "Put this game in dada!"
Acekard2 - Purchased in July, during the "bad batch" run, still working and currently my favorite, gotta love the menu!
Edge - Funky box... but it's close the the R4, does SDHC, and just works.
Acekard RPG - still waiting on it from Hong Kong, only been about a week, shows shipped at USPS
Gonna try out some of the others as my "hobby budget" allows...
Clone, knockoff, whatever... if it works, it works, me and my family can play Video Games Hero and all our backed up carts and i really dont care who made the card