Anybody upgrade their Zu Omen DWs to Souls?

Interesting. I had done the same with the 15 ohm resistors but with an NAD C368 driving them. As in your case it softened them a bit but didn't give me what I was looking for. I decided to follow the generally accepted path of lower wattage tubes resulting in a substantial, welcomed change. Your point about synergy between amp and speaker is well taken. I enjoy listening to this combination a lot. I would be just fine leaving it as is if i weren't for the full trade in value offered by Zu. 

@audiewww when do you expect the Souls?

I'm not sure exactly, but because the walnut cabinets are already on hand I was told they would be ready to ship in one to two weeks. I'll be optimistic and hope for end of this month.  

However long it takes, it's too long :-)

@audiewww I'm sorry to be such a pest, but do you have an update?!

The jury has returned and the verdict is in. Souls win! They needed a couple of weeks steady (10+ hours/day) break in to lose some treble grain, but thinking they had improved enough to decide I did a comparison with the ODWs this weekend and the Souls are very compelling. If you read John Darko's review of them it's pretty spot on. The ODWs are very good speakers, especially for the money, but the Souls are next level good. I had every intention of sending them back if they weren't worth the extra cash, but for me they are.