but if you have a number of transfer functions as I have, then I prefer floating point. <p>

All of these transfer functions are known, and should have a known gain and known precision requirements. I would guess that none of them need to make use of the full range a float provides, and therefore a long will make better use of the available bits than a float (provided that the designer is not too lazy to actually work out the numerics).

Not to mention all the numeric pitfalls that working with floats brings. Do you know the algorithm to "accurately" add more than two floating point numbers ?

I've dealt with transfer functions that had a really nasty internal gain ('t was a 0.05 Hz first order IIR highpass @ 500 Hz sampling rate. Nasty, nasty, nasty, I tell you), and still did it with fixed point arithmethics.