I have both setups and I can say that I never used mesh gear on the GS. I do use it on my street bike (HD) on hot days but not off road.
All my other gear has vents but the vents are not very helpful if you sit down on the bike.
I wear all gear off road regardless of temperature and it get hot. Drink plenty of fluids and you are okay. I also have a cooling vest that I use at times.
My suggestion is go regular style.