With the "fence and dog" method, you are at the mercy of the squareness of the hole pattern, which Festool does not guarantee. There is no adjustment this way, but it is the quickest, and most repeatable, at this investment level..... if the accuracy you get is acceptable.
The rail square is probably the next as far as quick/easy, but it doesn't use the MFT at all, it's a free-standing solution. There is no repeatability as far as multiple parts are concerned, you are still measuring/marking by hand, at this point.
The natural extension of this is a parallel stop system, which does give you the measured repeatability, but this is still not an MFT situation.
A hinge system would be next in terms of cost, but you gain adjustability for squareness at this point, plus you can clamp a stop to the table for repeated cuts. This would cost less than a fence/flag stop, which are not necessarily part of the hinge system, depending on brand and level of investment.
It's all about how deep you want to get with it.
