I own both the trollmaster 2 and the 3. The 2 is wired and the 3 is wireless. I have not used the 3 yet as that boat rarely gets out of the shop. Both units are setup on Yamaha 9.9 high thrust kicker motors.
I installed the 2 on my everyday boat because I didn't want/need an extra remote. Plus, I much preferred the dial throttle control over the worry of having to hit a button over and over again. I can say that I'll never own another kicker without one of these units. Whether it is i-troll or Trollmaster. It is very easy to really fine tune your throttle and repeat it.
That said, I will say that the yamaha kicker installation kit is less than be desired. It isn't the fault of the company but rather how the engine is built and the way to which they connect the throttle cable engagement. Mercury and some of the other units use a hard rod to connect from the servo so the sensitivity is repeatable every time. Say you are trolling at 1.3 and your setting on the control is 13, with those motors, you pretty much dial right back to 13 and you are at 1.3. With the yamaha, they use a cable with a loop. Although you adjust out the most play possible with the servo, that loop still has play when you go to the neutral position thus 1.3 "might" be a 13 setting one time and a 16 setting the next. Not a huge deal as you still have unlimited adjustment and fine tuning. Something that takes time trying to do with the hand throttle on the kicker.
I'm not sure about installing panther steer or some of the other options you can do with the Trollmast 3 as I really don't have a use for it as I use my bow mount for steering.
There was a Marina out of Florida that my dad ordered the 3 from that was much cheaper than most of the other places. I'll have to see if I remember to ask him the place. I ordered mine from Walmart.com believe it or not.