CoreTec is a click together vinyl plank that has a water proof core that is made from limestone/dust. This is a USFloor product that is brought in from Asia. Some CoreTec has cork underlay (1mm or so) and others do not. Cork is the thermal benefit you are looking for...not the vinyl.

The HydroCork is a new vinyl-cork product from Wicanders and it is a a drop-lock material that is a floating vinyl floor (manufactured and imported from Portugal). The middle layer is cork and it is quite thick (much more than 1mm). The cork is what offers the warmth.

HydroCork is allowed in bathrooms and is considered highly water resistant (same rating as CoreTec....your decision will come down to "like" rather than "better water resistance").

Knowing cork the way I do...the Hydrocork will offer more warmth than CoreTec simply because there is more cork. More cork = more temperature control.

Porcelain tile = bare concrete. As cold as frozen earth...not something I would want in my basement. In a cold climate I wouldn't go anywhere near it. You will avoid your basement during the winter months. Which means you loose access to your basement for 5-7 months a year.

Zencats, did you end up installing cork floors? I am in the process of researching options for my basement. I'm also located in New England and was considering Wicanders HydroCork and WeCork. Would love to hear an update if you ended up choosing one.