I don't know anyone who has the (original) Professional adjustable comb stock AND the 2.0 so this will be a true apples to apples comparison. Weights were taken with the stock only. The trigger group and bolts were removed. All the stocks have the aluminum receiver and there are no kickstops installed.
Intuition stock (22 mm inlet) 1364 grams
Professional stock (with two LOP spacers & 17mm inlet) 1559 grams, (est. 1484 grams w/o spacers)
Professional adjustable comb stock (17mm inlet) 1737 grams
Professional 2.0 stock (17mm inlet) 1380.5 grams
The only thing I didn't remove is the LOP spacers on the Professional stock. Each of the spacers add 37 grams for a 74 gram gain if you don't count the added weight for the longer screws. Minus 75 grams on the Professional stock, puts it at 1484 grams...about 100 grams (3.5 oz) heavier than the Professional 2.0. This is what I would call insignificant, but your opinion is your own.
Professional adjustable (1737 grams) vs Professional 2.0 (1380 grams) is 357 grams of difference. This is over 3/4 of a pound and it's very noticeable with one in each hand.
I find it interesting that my wife's Intuition weighs less than all of them. Trust me, I double checked this after writing it down and seeing the results. The removal of material from the forend had an impact on this, but I can't imagine it's that much.
My Professional 2.0 bare rifle with the iC bolt assembly with MA head, aluminum trigger group and 375H&H 17mm barrel comes in at 3303 grams, just over 7 lbs. Making it ready to hunt by adding a sling, 4 rounds of ammo and the AimPoint T2 w/ QD mount and it's 3852 grams, right at 8.5 lbs. This is what I consider a perfect African stalking rifle that's designed to be carried all day, but still capable of taking the largest game at ranges under 100 yards.
PS - I have a Swaro Z8 1-8x24 that I'll also be using with this rifle, but it's out for repair at the moment. It will add about 500 grams to the above total, but it's still very doable at 9.5 lbs for a complete hunting rig.