I'm not 100% certain, but I don't think the ReefKeeper can control VorTechs. That said, I'm a VorTech owner and a ReefKeeper Lite owner, and I'm very happy with both. I don't really think I've had the need to have my VorTechs to be controlled by the RKL. Then again, I have the MP40ws, you may not. I don't know if the ACjr. can control VorTechs or not.
For what you're looking to control / monitor, I would recommend the RKL Plus gets you the head unit, two 4-outlet strips (PC4), an input junction box (SL1), a temperature probe, and a pH probe for $279. I never really found the RK hard to program, but they just released their new software for the unit (I think they call it EasyFlow) that supposedly makes it easier to program.
The thing that sold me on the RKL was the fact that Digital Aquatics will allow you to upgrade to the Elite unit for basically the difference in cost between the two units. So, buy the RKL, use it for a while, and if you outgrow it or decide you need more functionality, send it back to Digital Aquatics, pay them $100 (or something close to that) and they'll send you a new Elite head unit.
In the end, I'm guessing either will probably do what you want. Which one you go with will probably come down to which you can get the better deal on, and you feel more comfortable with (i.e. maybe you know somebody that has one or the other).
As a note, in my research on the message boards I found the RK vs. ACjr. argument to be pretty polarizing. Like the Xbox360 and PS3, you have people that are very passionate about each unit on both sides. So, be sure you take some of the opinions (on both sides) with a grain of salt.
Good luck!