Cells survived after G418 selection are transfected cells? - (May/15/2006 )

I transfected cells with my plasmid which contains a G418 resistant gene. After 3 days of treating cells with G418, many cells died, but still a lot survived. But the control cells which were not transfected all died. Are most of those live cell sucessfully transfected with the plasmid (no matther they are stably transfected or just transiently transfected) ? May I use this way to sort transfected cells?

Is there any other label? Only G418 resistance? I think it is better to confirm by another label.

3days only of selection... hmmm well i don't trust a selection by G418 under at least 15 days, but in general it's 1month.