So I'm about 15 sessions into my learning curve for windfoiling, after decades of experience windsurfing (but none for the last 10 years).

In February, I purchased a Starboard Foilx 145 foil board with a Slingshot i76 foil. To aid in my learning curve in the light winds where I live, I purchased an i99 wing for the Slingshot, and I've found that to help by slowing things down as I retrain my muscle memory, stance, and balance for foiling as compared to windsurfing.

But even with the i99, the Starboard Foilx 145 still feels kind of squirrely underfoot. I've been experimenting with footstrap positions, mast base positions, fuselage positions (A, B, and C--I use C with the i99, and B with the i76), and I'm slowly getting better, but I'm nowhere near being able to gybe.

So my question to those of you with more experience is this: would I be better off using one of the Slingshot boards during my beginner curve, or should I just stick with the Starboard FoilX 145 and aim for more TOW?

More background: I weigh 75 kg, and I'm 59 years old. Any suggestions are welcome.

I haven't ridden the FoilX, but the 145 should be a great board to learn and progress on based on your weight and board dimensions. You won't gain anything by switching to a SS board.

Just TOW and you'll get the gybes sorted. In my experience, my full foiling gybes were not consistent until 1000+ attempts (counted by a GPS app). The best way to learn the foiling gybe is to make as many attempts as possible. Try to gybe after a minute of sailing or less. Yes, you will crash a lot, but it'll get easier and easier with time.

I am not a talent.

You already have good gear. Just get a lot of TOW, or, rather, TOF (time on foil).

Jibing on the wing is overrated. You can do just fine by coming down off the wing and then doing a regular windsurfing jibe, either carving or pivot. That's all I ever do, even after 285 sessions on a foil over the past 4 years. I will be working on the full foiling jibe, but it is not really necessary.

It may be that you are still in windsurf position instead of windfoil position. If you are still leaning out and putting a lot of pressure on the rails, the boards will feel squirrelly. Even wide windfoil boards can turn quite quickly on the wing like a 100 l. freeride board. Windfoil stance, especially as you are starting out is much more vertical over the board and it's perfectly fine to have the back foot in the middle of the board and not use the back straps at all. It's only when you are more comfortable on things that you may wish or need to be out on the rail leaning out like the classic windsurfing position.

Another thing that may be contributing to your discomfort is that the i99 has a center of lift further back than the i76 requiring more back foot pressure. Make sure you compensate when switching between foils by moving the sail mast base backwards and perhaps raising the boom a touch.

As a separate note, I'd hesitate to call jibing in the air over-rated. It is the key to light air and underpowered happiness. It certainly isn't necessary but once you get to the point where you can avoid touching down (or minimally as possible) in low winds, the carnival ride never ends. I can often jibe in winds lower than I can pump up on to the foil. I'd much prefer to jibe than to spend my time pumping. Jibing in the air when powered is just plain, stinkin' fun, too. I love cranking into a nice, powered flat water jibe with a small sail - what a lovely feeling. And, when the water choppy or in a swell, not having to be on the rough surface is nice, too. Again, none of this is necessary but it's like the icing on the cake.

And, when the water choppy or in a swell, not having to be on the rough surface is nice, too. Again, none of this is necessary but it's like the icing on the cake.

I agree - icing on the cake. I am about 90 sessions in and a few weeks ago sorted out flying jibes. I only sail in chop and swell so they are not always pretty or successful but when they are it is the coolest feeling.