I went to both livigno and Pamporovo last year. The snow in Pamporovo was appalling last year worse than any other. Price wise you won't find a great deal of difference between Livigno and Pamporovo. Pamporovo has hiked the prices every year as they are now comparable with duty free resorts like Livigno. However even with good snow Pamporovo is a much smaller ski area than Livigno and pound for pound Livigno is much better value for money.
Nobody on here is saying that Bulgaria is better or worse than anywhere else, most of us just happen to love Bulgaria - so why people come on this board with the sole intention of talking it down is totally beyond me