It's cool to have the actual cart, but thanks to the 3DS eShop you can get its 175 unique puzzle rooms, 8 cleverly-designed bosses, and about 10 hours of game play for a mere $2.99. It's a ridiculously good deal (eShop page).
I have the cart, but have not purchased any eShop GameBoy games yet. Do the titles on the eShop give SuperGameboy border/color options? Or even the GBA color pallets?