Their failure would involve an uncomfortable and expensive rethink for an industry that is worried enough as it is.

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But most 3-D effects on the market still require users to wear glasses, which some complain are uncomfortable, expensive and nausea-inducing.

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They may be uncomfortable, some are expensive, and in all cases the results take time to come through.

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The downside is that it's more expensive, uncomfortable to wear for long periods of time and has to be custom fit, Reingold said, so it's suited for people working in high-risk laboratories.

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Travelling is expensive, time-consuming, and (in coach, where we startup types fly) uncomfortable.

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