You also have to look at what this gig and other future ones will pay you. It's important to be realistic about buying gear that reflects your finances. Buying a 2192 which costs in the mid $2,000's for a gig that pays a few hundred is probably not justified. However, if this and potential future gigs will easily get you over that amount, then you've got a more of a reason to go high end with it.
The Rosetta is less expensive, as is the Lavry black series I mentioned earlier.
That said, you mentioned that price is not an issue. But the thing about price is that you would have the extra money to spend on something else if you got a less expensive converter.
If all or most of your work is soft synths, then a converter is much less important. Depending on your sound card, I still think you need a nice one for any acoustics you record. But I don't think it is necessary to go all out. You will be absolutely fine with a UA, Apogee, or Lavry converter. Any of them will do a great job.