From what I remember from my time demo'ing it, Trueverb really isn't your typical reverb and I wouldn't consider it as an alternative to Lexicon or Valhalla.
It always stroke me as putting the emphasis on the spatial/room aspect of things, rather than on lush tails and such.
Not that you could do that with other reverbs, as long as they let you work the early reflections and all of that. But Trueverb seemed to me to be more akin to the old Cakewalk FX3 Room Thingie. That's my perception of it, anyway.