You're going to get too many answers. I would say go with Nirvana or Mandala. I've not grown Mandala, but have heard many good things. I HAVE grown Nirvana (Blue Mystic last grow and Bubblicious/White Rhino this grow) and have been very satisfied so far (though I admit, not much data to go off).
That said, other breeders have cheaper seeds too. The Pure from TFD is a relatively inexpensive, killer strain.
That said, other breeders have cheaper seeds too. The Pure from TFD is a relatively inexpensive, killer strain.