Have read and read and read all about the following seats Mustage Vintage Wide Solo, Mustang Wide Tripper Solo and Sundowner Solo max i would likely do would be 500kms in a day maybe twice a year otherwise max 100 in a day once a week i also dont want the seat to sit me any closer than the stock seat - Any opinions on what would best suit me - 2013 Fatbob with 115kg rider

Mustang wide vintage solo with detachable back rest. Will be more comfy than the tripper. Similar comfort to the sundowner but the detachable back rest on the mustang makes it better and more comfy on long trips IMHO.

I should also add that if you don't like the cumbersome look of the wide vintage tourer or sundowner the mustang sport tourer is a good compromise between comfort and looks.

Don't know if any of those seats offer a reduced reach option but when using the back rest it pushes you forward a bit. You could also consider a change to risers or bars for your reach issue.

Stock position feels ok dont want to get any closer would feel cramped - also looking for a solo option that either keeps me the same or pushes me back a little