I have two 2022 V7 850s. A Stone and a Special. I can now say from experience the Special’s brown ribbed seat is quite a bit more comfortable than the Stone’s black seat. They are, of course, styled differently. The foam in the Stone’s seat becomes compressed by my 110kg in about 50 miles. So far the Special stays supportive all day. I wonder if they make a black seat for the Special and if so will I need a mortgage to buy one.
I can recommend this service:
They did a great job when they rebuilt the seat on my California, which had compressed after 20 years of use. They use memory foam and can add more or less to your requirement. The result was excellent. The bill came to £200 as in my case they had to recover the seat and do stitching. However, depending on how much extra foam you want, they could re-use your existing cover which would be considerably cheaper.
My seat is all-day comfortable now.
They do a mail order service, but if practicable it’s best to attend in person and they do it while you wait.
Worth giving them a ring and see what they advise in your case.
I did recently get a black gel seat for my Special, as the stock brown leather one is still a it too hard for me, takes more than 50 miles tho. 
My main issue with it, is it’s leather, so I have problems with mould during winter, and was constantly worrying about getting it wet. It got regular waxings with Duck Wax (that is also an extra chore!), but still doesn’t stave off the mould indefinitely.
The item is ‘Moto Guzzi V7 Stone/Special 850 Comfort Seat Std’
It came from Rider Gear (Shepherds Bush). They said it had to be ordered from Italy.
It’s OK comfort wise, no worse than the original anyway. But not a massive difference.
£270+ -ish believe it was.