One thing that is being overlooked in this thread is that the IIFT that comes with the 2nd edition ASL rulebook is, in terms of graphic design, the worst-designed table in the game. It is essentially unusable in its current form.
Specifically, it has NO shading of alternate horizontal rows, which makes reading a result in the middle of the table an exercise in total frustration.
So if someone says "I tried the IIFT in the 2nd ed rulebook, hated it, and now I will only play with the IFT" they'll get no argument from me. If my first exposure to the IIFT had been through the 2nd ed rules, I probably wouldn't be using the IIFT either.
If anyone really wants to try out the IIFT, they should get the version that's available on Ole Boe's web site. It's much more compact and as easy to use as such a big table can be. And for those who prefer the IFT, Ole has a neat version of that as well.
http://home.no.net/oboe/
To answer this thread's question, I've used the IIFT ever since it was first published in the 1989 ASL Annual. It is big and unwieldy... but the game just plays so smoothly when you don't have to constantly shuffle units & SWs around to try to match your FP totals to the IFT columns.