Actually the MX and most GF4 and under series are terrible for 2D quality, but the question is whether you will care enough to pay for more. It doesn't require much more to get better. A cheap ATI R9000/9100/9200 series card would do fine (even an R7500 will be better than the MX), also a cheap nV FX5200SE would have better 2D quality than the MX, it's not about the power of the 3D but the quality of 2D. A better choice still would be something from Matrox, even an old G450/550 would be better than the MX, and the P650 would give you the best 2D for the home market. However, the question is how much it matters to you. You will be able to do everything you need to for basic Photoshop, etc. with an MX, but for truer colours and better quality picture, a better card (not a top of the line gaming card) would show better image quality and truer pictures.
An R9200SE goes for about $40US, an FX5200 is about $50US, and you can find G450s for about $50US, and a P150 would be about $150US. Of course prices vary wildly from deal to deal. (the R9200SE/FX5200 and P650 prices are from NEWEGG just for reference).
You can always try running with the MX and see what you think of the picture quality. Although you really won't notice the difference until you see the others.
If you are aiming to focus on picture editing and replacing your film with digital at home idea it is worth the upgrade, if it's just a hobby and for fun and the occasional touch-up and basic viewing, the MX will show you the basics.
- You need a licence to buy a gun, but they'll sell anyone a stamp <i>(or internet account)</i> ! - <font color=green>RED </font color=green> <font color=red> GREEN</font color=red> GA to SK