You can get a free demo of the ONTOP sim on the net. It runs for about 10 minutes, then nags you for a minute or two, then keeps running. Demo verision is limited to a couple of airports, but they do have ILS. Also there is a 5 or 6 diff planes, up to small twins.
I haven't seen the latest flitepro. I have an older version (6.3), and it is terribly over sensitive
If you have an opengl video card, I would recommend X-plane. Very smooth graphics, as the program 'takes over' the whole system.
If you have a fast internet connection, or a lot of patience, download the demo at x-plane.com
Mike