Rex is right, it is totally overpriced. The kicker is that you need a CO2 bottle as well. To give you some ideas for normal prices:
All-in-one regulator (contains bubble counter, solenoid and needle valve) - ~$75
CO2 bottle (10lb) - ~$100
Check valve - sometimes included in AIW regulator, sometimes ~$15
Reactor - build yourself one and save big $$
Tubing - ~$0.50/ft
(you can get things a bit cheaper if you know where to look)
That deluxe system does contain a pH controller, but it is questionable if you need one or not. Do some reading on this site, there are many discussions pro/con. I think unless your water is extremely soft, a controller just adds unneeded complexity.