Fixed-point arithmetic essentially gives you more resolution at the cost of not having a dynamic range, so in practice you reduce some round-off errors, but overflow errors are much more likely. Overflow ends up as saturation in the context of audio editing and usually sounds like really bad clipping.

In practice, fixed-point or floating-point is better depends on the operation you plan to use and whether you have a good idea whether you'll be able to stay in a fixed range ahead of time [1].

[1] The loss of 'footroom bits' corresponds to the extra resolution lost whenever the FP mantissa increases - http://www.tvtechnology.com/audio/0014/fixedpoint-vs-floatin...