Can anyone recommend it and would it be fast enough to process shooting in full HD on a Canon 7D? ...seems to have positive but mixed reviews on Amazon.
Also, my laptop seems to have a max of resolution of 1680x945 (I could be wrong but this is what the display seems to show as max on screen resolution option by right clicking on the desktop and clicking screen res) but it plays blu-ray so doesn't that mean it's full HD. Would this system have problems playing videos shot from the 7D?
Here is my two cents.
1. Speed of card - will work fine. I run (home/work) with UDMA 60MB/s SanDisk cards. So you shouldn't have any issue with HD capture on this card from my experience.
2. Size of card - we work with 8GB and 16GB cards as a rule to reduce overheating of the camera. While you can get more on the 32GB card, it matters little in real production as you are always capturing with a ~12min clip anyway. So it is easy to change out often. Moreover, having smaller multiple cards allows you to work faster as you can be shooting while a card is being downloaded.
3. Laptop: Your resolution is probably the least important tech spec to playing back HD video. The resolution on laptops are a limitation of GFX card and screen size/layout. If you are playing Blu-ray you probably can play back the 7D footage, but the specs of RAM, CPU speed, GFX memory, etc. are far more significant factors in playback.