Saw some videos for Tower!3D Pro on Youtube featuring Jeff Favignano and Bay Area Buggs. Have always been interested in this sort of thing, and when I saw it in action, I knew I needed it. Took me a few weeks of sticker shock to finally purchase. Ended up getting a few add-ons since. Other than some quirks relating to gameplay (commands that would streamline runway crossings, aircraft taxi speed after landing roll on runways, aircraft refusing to exit runway on correct side, random spinning on runway entry and pushbacks, etc), I am very happy with this purchase. I usually start playing, and 4 hours happens before I realize it.
On a side note, I would love to see an airport like PANC (Anchorage), where you get 2 parallel runways (typically used for landings with occasional takeoffs) and a crosswind runway without intersection used for takeoffs.