i have just started using virtual DJ ive not used any others so cant really make comparison, but what i will say is virtual dj is easy to use and so far reliable!
the samples are good, i done a 21st last weekend, beforehand i lent the parents of the birtday boy a digital recorder and got them to record birtday greetings from various friends and family and then saved them as samples and dropped them in over the music at various intervals throughout the night! it went down really well!