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The answer (as usual) is "it depends."

I'm a big fan of balanced myself, if done right. And that means a true balanced connection with separate + and - phases, not just a single ended signal on the XLR connector. So, the first thing to check is if the Bifrost is "truly balanced", does it use a different DAC for each phase? and if not then you might as well stick with the RCAs.

If it is, then you get into the trade-offs. Getting a Decware transformer for your balanced input isn't cheap, either in built into your amp or as a stand-alone ZBIT. But a lot of people really really like them. I took a different approach myself, instead of using a transformer to convert the balanced signal to single ended, I bought two UFOs and use them as balanced monoblocks. What that means is I'm using the left and right channels of a stereo amp for the + and - phases of a balanced signal and amplify each phase separately. That is different then the transformer which differences the + and - phase into a single ended signal before it is amplified. The two UFOs don't cost that much more than a UFO2 with the balanced connection and you get a few extra watts bonus.

I don't know if this answered your question at all, or just made things more confusing. Good luck in any event, in the end you've got to decide if it is worth the $$$.

I can't comment on the performance, but it is sure a spendy mod!

Also interesting this balanced ins are not an option on many of the other products - no idea if they means anything, just an observation.

When my brother was ordering his ZMA he was going to get the XLR transformers built into it. Steve suggested using a ZBIT. We both agree that was the better move.

I'm also in the camp of use the best tool for the job. If noise isn't an issue RCA is better in my experience. Some industry professionals say to always use XLR if it's available. My experience and others say this isn't true.

My view is try both. I usually prefer RCA.

Gain riding this changes a things. If you are using XLR because you can get more gain usually 2v RCA 4v XLR then things change. I have a PS Audio DSD and output is 1.414v RCA, 2.818v XLR. I prefer RCA out still. I've tried running XLR -> ZBIT -> RCA -> CSP3 and prefer RCA all the way. If I didn't have the copious amounts of gain with the CSP3 I might prefer the XLR -> ZBIT -> RCA -> AMP combo.

Currently I don't have XLRs in my system and the ZBIT it resting. I'm holding onto it as it's a good tool to have when appropriate.

Galen Gareis a cable designer talks about RCA vs XLR in the following link.

https://forum.psaudio.com/t/rca-vs-xlr/14787/19