They’re amazing. Thermoform stiffness/performance for slightly less money and less weight and amazing portability. But you have to weigh the puncture risk and poor wind resistance.
I like it because they are just so… different in their handling. Lighter than even CF layups, and the most stable boat I’ve ever paddled by far. Initial stability doesn’t compromise final, you have near infinite levels of both, the air doesn’t want to sink nor tip, ever. Yet it’s so “airy” it doesn’t float, it flies over the water. How can anything so stable be so fast yet playful? Waves and current not a problem, just stay away from sharp things and wind.
Being “stable” is not a priority for me. I am used to light boats --the heaviest one I have now is 45 lbs and the Grabner at 33 pounds is 5 to 10 pounds heavier than the 4 of my 7 current boats that I use most often.
The Grabner sounds as if it performs like my first folding kayak, a Feathercraft Kahuna (14’ 9" x 25" x 35 pounds.) The Kahuna was a pleasant boat, very stable, but sluggish, tended to windcock and kind of boring for me eventually.
The appeal of the Grabner for me is what seems to be rapidity and simplicity of set up for warm weather day trips. I suspect it could not perform as well as my Wisper, Quest 135 or the skin on frame. But I would be interested in trying one out sometime, just to see how it feels.
I think if you’re used to high performance then no, the Grabner probably won’t impress. What makes it appeal to me is that for the money it is so light so my kids can carry it, and folds so quickly (2-3 minutes assembly!) and for how stable it is offers really good performance. It’s the most stable boat I’ve ever used, even more than a sit on top, and the performance is pretty middle of the pack even compared to serious touring kayaks. Do remember that I used the Holiday 3 which is a little heavier at 43 lbs but also longer at nearly 18 feet and much faster. Another perk for me is that both my kids can come paddling as it’s a 3 seater.
I tend to shy away from high performance because that means high instability. While thin and in good shape, I am also tall, unsteady and no matter what I do uncoordinated. I was born that way. My mom is my equal, she too is light as a feather, but stiff as a board, it must be genetic!
Did 9 whole months of yoga and I still couldn’t touch my toes. I’ve been paddling for 15 years and have yet to roll or rescue as it requires too much flexibility and coordination. Plus I hate getting wet. So I will never do the high performance thing. Ever. The “recreational” Stellar boats are about as high performance as I care to take it. In this sense the Grabner is amazing because it gives absolute top primary as well as secondary stability (they are not mutually exclusive in this design) with decent performance. Not only are the primary and secondary stabilities not mutually exclusive, but neither are speed and stability which is what I find so neat about it.
Understand why you crave stability, considering your body metrics. I’m the opposite: long legs, short torso (low center of gravity) and due to life long dance, yoga and martial arts training I’m pretty flexible. I feel very relaxed in my 21" beam kayaks. I also don’t mind being wet – good thing since I use Greenland paddles 95% of the time and they ship a lot of water.
I did seriously consider that Grabner tandem so I could take some of my more timid friends and relatives out in it. For instance, two years ago I spent a week at Lake Tahoe with a friend who swapped her time share for a condo right on the water. Rather than the hassle of taking two of my folders (extra baggage and she is a novice who was uneasy about solo paddling on such open water) we ended up renting a tandem sit on top while there a couple of times, but that was kind of inconvenient since it limited the location and scheduling of the outings. If I had a lightweight tandem to bring along I think we could have had more fun.
I go with two pumps- electric (I’ve used the coleman with the built in battery, one that hooks up directly to the car battery, and have one that uses dc from the cigarette lighter type port). All of them can get the job done up to a certain point, then I “top off” with hand barrel pump. The “electrics” don’t have enough pressure to finish the boat off. You may want to make sure your valves are all the way open, some valves have two positions- one for full inflation (pushed in), and a setting for topping off (the center of valve is out).