I used it a couple of years ago for a stained-glass project. I really liked it. I needed it to be really flexible to go around small corners, and it worked great. The tricks that I remember were 1) get the little finger iron press. It's like a finger cot for one finger that is made of heat resistant material so you can iron right up to the edge of your finger without getting burned - I've seen it in Clothilde and jhittlesewing and other places. and 2) when the project was complete I ran a line of stitching over all the tape to make sure it would stay secure. It probably would have been fine, but this was the first sewing I'd done in 20 years and I wanted to be sure it stayed. and 3) buy at Joanns when you have coupons. It's not cheap. I'll try to attach pictures.
Completed wall hanging
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Individual squares
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