I've seen SU-27s a few times in the air and on the ground here in Australia. The Indonesian air force has them and they have visited our shores as part of exercise 'Pitch Black' in the past, and probably will do in the future.

MiGs are not 'top secret' jets behind the iron curtain any more. Lots of friendly Air Forces have them now (India etc.) and they routinely co-operate with western forces on exercises.