Part of the reason I seem so critical of you is that you seem to be going out of your way to pick bad carts.
Let me show you how easy it is to find the right one.
1 - Go to nds-card.com.
2 - Click the "R4i Gold" section on the left.
3 - Click the "R4i Gold Card" section (since you want just the card, not a bundle).
4 - The only result is the right one.
http://www.nds-card.com/ProShow.asp?ProID=149
An Acekard 2i or DSTwo is a good alternative, though the Acekard has contact issues you might have trouble with.
I wouldn't use any free MicroSD, they tend to be really cheap models and you can easily run into problems with them (games lagging or crashing) because they often perform much, much worse than other models.