I haven't tried the Shakti alto, but I did recently get the chance to try the Narayan tenor, and I wasn't that impressed. It looks nice and plays ok, but I wasn't thrilled with the ergonomics, especially the pearls, which are convex, making the horn feel bigger than it really is. It's also an unknown quantity, so I don't know how well it lasts. The 62 has much better ergos and has been a decades-long reputation as a solid, well-built, ultra-reliable workhorse. It's not my favorite Yamaha, but it won't let you down. The Shakti may very well be a great horn, but I wouldn't buy a brand new, untested Taiwanese-made boutique horn sight unseen. If you can try them at a shop before you buy, that might be a different story, but if you're ordering something online that you can't play first, go with the tried-and-true option.