The chisels I make are made to take the shape of cutter that is fitted.  I find that if you make a universal shaft that takes all shapes of cutters there is a tendancy for the cutter to eventually drift out of true.  There is also the problem of continually changing the cutter and this can cause damage to the head of the screw or threads. From my personal view I would rather pick up another chisel to do one or two cuts rather than having the bother of changing the cutter, which is why I have kept the price at an affordable level. 

As for using the chisels, I prefer to slightly roll the chisel to the side to come in with a sheer cutting action to start the cut and then roll the chisel as you require to cut more aggressively.  A lot does depend on the wood used.  When working with softer or green wood the chisel can be used quite aggressively but using on a piece of hard kiln dried wood such as oak, then a gentler approach is needed to avoid the nasty catches.  The carbide tips I use are designed for cutting aluminium as well as wood.  I like them as they give a cutting action rather than a scraping action.  This is not to say other carbide tips cannot be used on it as it is down to personal choice and preferance.