If you want to review a camera you need to do that in the country you live in. So if you live in England you choose Sony UK or Canon UK etc.
Most camera reviews (websites) are from the USA which have a tv system called NTSC with a framerate of 29,97/24/60 etc.
If you live in Europe tv system is PAL and we use 25 and 50 fps.
So there is your difference.
If you do not know which sequence setting to choose drag a clip from the Project Window into the New Item icon (at the bottom of the PW). It will create a matching sequence for your footage.
To edit AVCHD you need some horse power.
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