The current 840 vanilla is TLC, as others have mentioned. It has no problems, and in fact is a really excellent entry-level SSD. It's stable and very well rounded, and the EVO looks to continue that trend. Good quality TLC is fine for a consumer drive.
If it was low-grade TLC, with a poor controller and bad firmware, by a company that doesn't know what they're doing, that would be a different story. But the Samsung 840 series (and older 830) are good across the board. The Pro is much better for really demanding workloads, but for your typical consumer (content consumption, including gaming) PC? Even the TLC 840 models are fantastic.