I also have a TF10 quad from Unique melody and recommend you go through them and save some money. They can upgrade your TF10's for $275, whereas you'd pay $1100 for UE11's. Prices may have changed, but I'm sure you'd research that first. Heck, you could even go for a 6 driver upgrade and save over $500.
I never heard a UE11, but was able to compare my quad to a stock TF10 back to back. There was no question that there was a big improvement in forward mids, but detail through the mids and highs was improved. I think the soundstage might have suffered, because the vocals were brought in so much closer.
Overall, it was a huge improvement in sound and I was quite happy with my investment.