Routing Pro Tools To Hardware

Hello,

I recently invested in some outboard gear (bus compressor and 2-channel EQ), but it hasn't arrived yet and I came up with a question I've never really thought of before.

I am using Pro Tools and usually I will route individual tracks into stereo aux tracks for sub-mixing, and from there the sub-mixes are routed into a stereo aux master where I apply processing on the entire mix.

So what would be the main differences between routing the outputs of the sub-mixes via stereo line out into my outboard hardware chain vs routing the output of the stereo aux master (without any plug-in processing) line out into the chain?

I guess I am perplexed because it seems I am summing in PT regardless. Is that correct?