Not really a fair comparison, because Dwight is a league between the other 3 players. You'd have to find a much worse PF than Smith to make it a fair comparison.
You should have mentioned with Asik/LMA you'd have another ~$10 million extra to spend on another player.
When I hear twin towers, I think of two guys that can play center on the court at the same time. A guy that is a natural power forward is not a tower.
I picked Asik / LMA because the problem with this team is not that we don't have a good center it is we don't have a good PF. LMA would be an awesome addition to this team. Howard may be too but there sure is a lot of baggage that comes with him considering his "Dwightmare" tendencies when he is unhappy and his bad back.