Fonline engine is better than Fallout 2 - you can make faster, better and easier maps, dialogs, quests, scripts and all other things what you want. As Jimmy said, you should try play The Life After FOnline SDK - it is similar to Fallout 2 because there are these same world, locations and extra few other.
If you want play role play with friends in Fallout 2 world sdk is recomended for you. You can make character what you want and have fun. Try it - it will be very good.