I have the Chupa and had the luxury of playing a friends Yeti just recently.
1. Build quality is absolute top notch. Nothing to worry about in that aspect I can assure you. DM me if you want gut shots of my particular amp or have any serious concerns about the build quality.
2. The Chupa has the ULTIMATE hot rodded Marshall Plexi tone at a "discounted" price. Its what I wished the Splawn QR was, and for different reasons than the populous. The Chupa has one of the best MV's I've ever experienced, unlike the QR. The amp is glorious at all volume levels.
3. While I'm more than happy with the Chupa, I get why the Yeti is more popular. I have to admit I like it slightly more than my Chupa. Its more modern and tighter. However, if you crave more of that VH tone like you mentioned, the Chupa is your ticket. It excels at vintage Marshall tone and then some.