the problem with 1000' and below is the military boys - how many times have you been directly underflown by helicopters, transporters etc....... I know I have been spooked a couple of times because of how late you sometimes see these things.
But not at weekends and not generally in very congested areas. They have more sense than that.
Most VFR traffic seems to try and stick at 2000 feet on the nail. Most unwise.
QDM