The Keystoker factory install option will come with a modified Coal-trol Standard. For Keystoker we add an interlock input on the side of the control box which they hook up to their direct vent fume switch (if it is on the stove, of course). You can request the Standard+ if you wish.
And while I certainly would recommend the Coal-trol on its own merits (I'm a bit biased
), there is also the cost factor. As a factory installed option you will be able to save probably at least $100 off the cost of purchasing it later as a retail product, plus you don't need to do the rewiring of the stove yourself. I don't know the pricing of the option for Keystoker, so I don't want to be too specific on what you can save, but the retail list price for the Standard is $325 and you know what the option cost quoted to you was. Make sure to throw that into your considerations.