Is there any heat issue with Lenovo K3 Note ?

No heat issues have been reported so far by Lenovo K3 Note users. The fact that the phone has a MediaTek processor could be a reason for worry, but it is too early now to predict anything related to such issues. However, you can avoid getting your phone heated up by following some precautions.

I used Lenovo K3 Note on a promo at a Lenovo dealership. There were some games installed on that phone one among them was NFS Most Wanted 2 which is considered as a very high end android game. I played that game for about 20 minutes and didn't see any heating issue. I can't say that it doesn't heat just by using it for 20 Min. You can further read reviews on GSM Arena about the phone by its users.