F2A 256MegaBITS USB is the best bet for emulation, import it.
I'd recommend SUCCESS-HK.COM simply because you can pay with PayPal
at no extra cost.
XG are rubbish, the best alternative is EZ-F aka EZ-Flash Advance.
Note that there is also EZ which is a different thing to EZ-F....
See the emuboards site in my sig for loads of flashcart info.

The advantage with F2A is it supports a program called Pogoshell.
Pogoshell is a GUI like Windows that works on Flash Carts and it
compresses save files so you can have many more than the 4 that
you'd otherwise be limited to.
It also allows plugins, and some emus are available as plugins which
means you just put the NES or SMS rom on the card and when you run it
it loads the emu plugin with the game running - the game doesn't need to
be precompiled to run (injected in emu-speak).
Pogoshell is great.

Another good thing with F2A is that all the other carts have rechargable
batteries for the game saves and they invariably run down and lose the
saves without warning - XG have a bad reputation for battery problems.
The F2A has a long-life lithium battery that will run down and need
replacing eventually but by that time you'll not really care too much,
we're talking years.

I love Winning Eleven too - what do you mean by "patched"
Winning Eleven by the way?