I have never found a melodica with a precise tuning from the factory. I’ve owned a Suzuki Pro 37v2 (the previous model, which is basically the same as the v3) and the tuning was a little better than the Yamaha ones, but I didn’t think it was good enough considering the price. Actually there’s only melodicas tuned well enough to play, they will never be perfectly in tune. I would say that the best thing you could do is to learn how to tune your melodica.
Yes, Jon Baptiste plays a Suzuki Pro 37v2. Personally I think the tone of this melodica is very shrill and nasal. What can’t be denied is that it has a loud sound.
In terms of cost-effectiveness, I would take the Suzuki Melodion M-37C. The build quality is very good, as the key action and tone too.