Dip Station: Parallel Bars or Diagonal?

I'd really like to know if I should have a parallel bar dip station for the exercises in Building the Gymnastic Body. I have a diagonal-style dip station from Body Solid, but was wondering if I should get a parallel-styled one since that's what they seem to exclusively use in the literature. I didn't know if the difference in style would get in the way of progress because of how the shoulders are positioned when using the diagonal bars vs. the parallel bars.

The diagonal style will certainly get you going.

The angle is more a matter of what you are used to for most of what is done on GB.

I''m not sure how they will work for you with Russian dips for example, but i just don't think its a deal breaker.

The issues if find are more with swinging elements like swinging dips, are the bars high enough and is there clearance in front and back? You might have to adapt your technique a bit to the peculiarities of the style of system, but i believe it should serve your purposes and as time goes on you can consider something else.