I played a lot with tube tech eq and summing mixer and softube counterpart and was able to get similar results (at least to my imperfect hearing). However I wouldn't go as far as saying it sounds better. Personally to me the best thing about outside summing is ability to plug in hardware EQ out of the box before summing mixer and push it, without ITB gain staging headache.

Not all plug emulations like to be 'driven hard' some have been designed to give 'that analog sound' at normal levels not when driven, so they may sound weird or unpleasant when pushed. If you use high quality plugs and maintain proper gain staging all along you should achieve similar sonic qualities. I would only consider external summing mixer if you want to use hardware (or already got hardware) I've recently 'demoed' Tube-Tech summing mixer and Dangerous 2bus with some nice hardware EQs. Your best bet is only that the signal coloration that VCC does, would lead to something that sounds more or less similar to a LFAC.

A LFAC or a summing device with 32 channels electrically sums 32 channels and VCC on 32 channels in your DAW doesn't sum anything at all. My friend and I (a bass player who also mixes) looked at each other and said 'wow, this really does sounds like VCC!'Not at all. The other day I was tracking in a room with a Neve 8078 board, which we were of course listening to playback on. Unless you have really great DACs, its diminishing returns. The Dangerous stuff by contrast doesn't add any crosstalk, and in my opinion most of the change in sound/degradation comes from the DACs. The cross talk of VCC completely changes the stereo field of a mix much like running through a board would. A summer doesn't sum either, it only sums 8-16-32 channels of your signal, the DAW and the crosstalk of the DACs does the rest.

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