Abysmal. A pointless expansion that I would not recommend to anyone. Strategies that used to work well are now completely foiled by lucky draws from the massive-and-growing 300+ card pile. The new prestige mechanic is unbalanced and adds nothing more to the game than putting fines on Free Parking adds to Monopoly. There have always been some very powerful combos in this game, but the odds against more than one player achieving such a combo have increased to the point that this is virtually a pure-luck game now. Games that used to be close and exciting are now usually blowouts whose outcome is obvious after two or three turns.
I only rate it a 2 (instead of a 1) because some of the new cards are nifty. You might be able to selectively add some to your deck to spice it up a bit. The only other way I'd agree to play this wretched expansion would be if we could pull at least 75 of the most worthless cards (and there are a lot of worthless cards now) out of the pile before starting.
I have heard that the designers will be taking RftG in a new direction with future releases; I hope that it will be the opposite direction from this one.