The oversized monster jacks was true on some of their models, but it was rectified some years back I believe. The problem effected barrel type jacks which are much more prevalent in basses.
The audible effect of an instrument cable is electronically equivalent as an RLC circuit. Because of the nature of instrument cables the R-resistance and L-inductance is negligible. This leaves capacitance. This and only this can have an effect on the sound of an instrument cable, assuming that the cable is in working order. If you play an active instrument or an instrument with a buffered output( ie active basses/guitars, keyboards, preamp outs), then you are dealing with a low output impedance. This negates nearly all the effects of capacitance in the cable.
If you play a passive instrument (passive guitar/bass, microphones), then cable capacitance will have more of an effect because you are dealing with a high output impedance. The effect that capacitance has on a audio circuit is that of an low pass filter. It is the same effect as a tone circuit in a bass or guitar, minus the variable resistor. Capacitance bleeds high end to the ground. The higher the capacitance value the lower the filter frequency and vice-versa. Capacitance will also shift the resonance frequency of your pickups.
If you want the cleanest sound out of our passive instrument find a cable with the lowest capacitance per foot. There is no correlation between the cost of a cable and the capacitance per foot. Most high end cable makers do not even publish this figure. I personally roll my own cables, but there is no reason to spend over $30 for an instrument cable. Much more than that, and you are paying for marking hype.