I may be a bit biased since I make the Gambit but I’ll write about the triton since I own one. Haven’t played a kingyostar so I can’t help on that.
The Gambit is a killer Yoyo. It’s everything you could want in a yoyo: dead smooth, extremely stable, long spinning, great colorways and best of all under $100. It’s on of my favorite yoyos and I’ve heard nothing but good words about it and the reviews are out there as well. If you love an H/V shape and want a great bang for your buck a Gambit is IMO the way too go.
The triton is one of the best organic yoyos I’ve ever played. It’s big, floaty, long spinning and super comfy. Not really good for horizontal because of the shape but it’s awesome for everything else. Plus G2 is a great company to support. It’s the most expensive of the three but it plays great.
It all depends what shape your looking for. The quality is the same with both gambit and G2s being made by the same machinists. Your choice!