MMF is something you have to try a few times before you figure out what it supposed to feel like. Thank goodness it is so inexpensive to make!
For me, the perfect consistency is 16 oz PS, 16 oz MMs, 2 T water, 1 T glycerine. I worked with taste and came up with this recipe:
http://cakecentral.com/cake_recipes_rate-7262-5.html
It can get sticky if it is overheated when re-softening in the micro (just add cornstarch or wait til it cools off). It can get hard if you melt the MMs too long (60 to 80 seconds is plenty).
Weather also affects the outcome: In hot weather sometimes I need more PS. In humid weather I use less water.
So it is pretty finicky, but I've worked with it long enough that I've come to love it because it is so easy to roll out, cover a cake, and make figures with. And I love the taste when adding LoRann buter flavor (I now use 2 drams - my recipe states one dram).
Satin Ice is too dry and matte for me.
Fondarific is amazing for taste and for covering a cake, but not for making accents and figures (too soft).
I haven't tried FondX yet but one day I will, since it seems to rate better than SI and I can't stand SI.
Last week on AceofCakes Mary Alice read an article that was written about them in the local paper - it mentioned how gross the flavor of the fondant was. They use SI!