I picked up an AC20 combo with a G12H Creamback a few weeks ago. I had factored in the cost of dropping in an Alnico speaker like a Gold just based on my previous experience with 75W Creambacks. But so far I have no complaints with the speaker in this amp. This is my first AC style amp though and I've never played through an Alnico Gold, so maybe I don't know what I'm missing. If you've tried both, would you say a Gold would be a significant improvement?