I have a G-45 in my Sig 4*. Since the first tank its run very well. Low reliable idle (achieved on the second tank). It has the most minute of hesitation transitioning but I expect some of that has to do with the fact that I only have 5 or 6 tanks through it and it's not fully broken in yet. It was extremely easy to tune. I've idled it for several minutes on the ground, gassed it, and never had it sputter out on me. Super Tigre carbs were made before the 3D craze and were never engineered to be instant response carbs many people these days are used to. If you use them for what they were designed and engineered for, they are perfectly fine engines (i.e. not 3D) and a great bargain. I'd never hesitate to buy another one.