I think I'm with most others here.
I was contemplating buying a Retron 5, getting Japanese carts, then loading patches, but lately I have just gone the repro route. I have the Mother 1+2 with English patches (though the Mother 2 is incomplete) and Mother 3. I specifically chose the carts that were bright clear red (like Pokemon Ruby) to announce that they are repros. Just seems right, and I can play it on my original hardware. I'm thinking about doing the same with Seiken Densetsu 3 and Golden Axe 3.
On the other hand, I have also been burned by repros. Thought I was getting a sweet deal on a Final Fantasy VI Advance. I was even fooled by the case. Went back to it three months later and opened it up on a whim and found the black glue globs. The label was perfect, but the "Game Boy Advance" relief on the front of the cart is definitely "off".
So, I'm all for the "clearly labeled" or announced repro route, but am now hyper vigilant about everything else.
Anyone have recommendations for repros that would be worthwhile? I.e. games that are wicked expensive in your region or were never released?