Anyone had any experiences with Gaastra blueline vgrip booms? Looking at 200-250 size. Are they a good thing? Im 110kg. Sails 7-8m range.

haven't used the Gaastra but I use the Aeron v-grip. The v-grip is nice in the hands , allowing a comfortable relaxed grip. I also find the Aeron v-grip to be stiffer than a normal alumininium boom. A good compromise if you don't want to invest in carbon. You can check them out here... windsurfsystems.com.au/product/aeron-v-grip-alloy/

110kg, 8m sail, forget any aluminium boom.
Find a decent second hand carbon boom that will outlast a new aluminium boom.

Ive also got a sunshine mono alloy 170-230. Had gopro at tail of boom. It shows just how much boom flexes under gusts n chop. Maybe 20mm. Most of the flex seems to occur from backhand forward through harness lines to mast clamp. Amazing to watch it wiggle around like spaghetti, when under load.

As Red says, the Aeron V-Grip feels great in the hands and its really stiff for alloy. I'm close to 100kg and use the Aeron V-Grip 180-230 with my Retro 8.5m, there's plenty of stiffness without the added expense of carbon.
The V-Grip also comes in full carbon, windsurfsystems.com.au/product/aeron-v-grip-carbon/ which is probably the stiffest boom in the market.

Quick update. Ive gone with the Gaastra blueline 200-250. Salied it in a whole 5kts. Nice to hold. Certainly stiffer. Cant wait for some real wind n the ability to run adjustable outhaul.