I tend to avoid interpolation because it usually gives me a headache (especially in conjunction with 3D) but my LG LM7600 seems to have a good implementation. I've never seen any artifacting the few times I've tried it and the TV allows you to dial in the level of interpolation for both the horizontal and vertical using a sliding scale so you can really tweak it to your personal preference. If you have access to an electronics store that has an LM7600 on display you may want to check it out and see if you can play with the interpolation setting (LG calls it TruMotion). Hope that helps.
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