Levels 35, 50 and 60 I believe.
And yes, you can choose which profile to import, as long as that character has actually completed the game - ME2 uses the "New Game +" info so if your Shepard was lv55 when you finished, then you started a new game + and got it to 60, you'd need to finish the game again for it to be recognised as lv60.
And yes, you can choose which profile to import, as long as that character has actually completed the game - ME2 uses the "New Game +" info so if your Shepard was lv55 when you finished, then you started a new game + and got it to 60, you'd need to finish the game again for it to be recognised as lv60.