Having own/ed both a 4l manual and a 4.4l auto e31, my preference would be... the auto, which I think it is suited to the GT nature of the e31 (or is it a stage of life thing haha).
Don't get me wrong, the manual is the 'bees knees' and is great fun to drive (even with tired suspension lol), but the tiptronic auto is well matched to the 4.4l, smooths out the experience and is no slouch either.
Also, don't believe what they say about the e31 being slow, dull and disappointing. I find it a pure pleasure to drive and won't embarrass itself, especially the CSI, against most of the modern 'unmodified' stuff today. And it looks way cooler than anything else out there haha!
I thought my manual one had the edge, performance, handling and comfort wise, over the V2 Monaro CV8 I had at the the same time.
@Kodachrome If your CSI went to Christchurch, I think it is soon to be 'back on the road' from what I've read in a post on the US forum ☺️.
Cheers