My daughter was 4 1/2 before she stayed dry at night. If you look up night time dryness on the internet, you'll discover that it all depends when one's body starts producing enough anti-diuretic hormone, and that really depends on the person. Doctors won't even talk to you about it until the child is over six years old. Also, some children sleep so deeply they aren't aware of the signals from the bladder to urinate.
Some mothers swear that pull-ups keep the child from being aware that they've wet themselves. But I think these mothers forget that their mothers probably kept them somewhat dehydrated so they wouldn't wet the bed, like my mother did to me.
You need to decide for yourself what you and your daughter can stand. If you don't mind changing all of the bedding and doing laundry (and running up your water bill) everyday, then let her try the wetting herself process (I think she is way to young). Or, just use pull-ups until she starts staying dry at night for a couple of weeks, which could be next month or when she is five because it really all depends when her body and bladder are mature enough.