IMO the weakness in the Synergy heads are their transformers. I expected the 20w to sound small, and it's actually pretty good for what it is. I've A/Bed it to the 50w and they are quite comparable. This is not a good thing.
I've also A/Bed the 50w head to many other heads and power amps, and it always comes in last place. Granted it sounds good, but never as good as anything else I've put it up against. I'm sure Synergy is hitting a price point, not dogging on them. Seems to me like they could release a "prestige" 100W with legit iron, limit production initially, and see how it goes. And yes, an updated 50W is in order as well!