A GAN flagship isn't going to shave off seconds from anyone's solve times, compared to a decent modern cube costing a fraction of the price. It's not the same situation as the new Qiyi clock puzzle which, because its design and construction is so much better than existing puzzles, has reduced a lot of people's solve times significantly. GAN puzzles are very good, but not superior enough to the good budget puzzles we have today (RS3M 2020, Meilong 3M, etc.) to warrant spending $60-80 for it.
I like GAN flagships a lot, but I wouldn't necessarily recommend them to anyone unless they had plenty of money to burn, or could get them for free.