It's pretty nice.
I only use 2 modes... Economy (87 octane) and Performance1 (89 octane). Performance 2 requires more upgrades and minimum 91 octane.
I tried the towing mode, when I towed my TA to CA, but wasn't too crazy about it. I had better results shifting our of O/D when I bogged down. I never valet my car, so that mode is sort of worthless. If I ever park in a bad area, it's nice to take the key and shut it off, knowing that noone will be able to start it and probably couldn't figure out why...
After my transmission rebuild this summer, I should be able to take better advantage of all the modes. I expect a HUGE difference in power and performance, not to mention the economy of near 100% transfer of power to the rear wheels!
Edit: Forgot to add that it's actually only 5 stages as the 6 stage is "not used". I'm guessing there's a mod/upgrade I don't know about.