I've previously written about the Phoenix sim, which I strongly believe is the best for the money. One of the great things about Phoenix is the free updates. Currently they are at version 2.5, but 3.0 is offered on the download page as a beta product.
Phoenix is about the only reason I keep the Windows OS on a computer. Version 3.0 reaffirms that I'm going to have to deal with Windows for a while longer. The user interface has been reworked, and I find it much easier on the eyes. Function has also been enhanced, better widgets and on-screen indicators and a new toolbar system. Graphics have been enhanced, water spray, enhanced zoom for small models etc. Flying with buddies is now supported, as well as many more online flying options, including online competitions. You can now fly combat against AI as well, making for a very challenging game. This is just the tip of the iceberg on what has been changed.
Overall a great update from Phoenix. To read the beta change logs visit http://www.phoenix-sim.com/news.htm