The full game will be less buggy than the beta, but it's not likely they're going to be able to make drastic design changes in the short time between beta and release, and a lot of the issues people have with the beta would would require drastic design changes.
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Videos of the beta didn't even look bad to me O.o this game looks sweet
The biggest problems I had are with character customization. It's a pain to customize characters/karts compared to ModNation Racers and even LBP, and applying stickers sucks (especially in character customization). For this game to be the love child of ModNation and LBP, this is a huge problem.
Buuut, tons of people on the beta forum complained about this in topics and official polls, so hopefully it'll be fixed. :D
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