This morning I tested it (and it sat in a climate controlled garage overnight) and I couldn't turn it at all. I had to use channel locks to get it off and there was a huge WOOOSH sound when it broke the seal.
This is the replacement one that I have: http://www.roverparts.com/Parts/NTC5418
The OEM one never had that problem
This is the replacement one that I have: http://www.roverparts.com/Parts/NTC5418
The OEM one never had that problem