I recently decided to update my audio interface from a Edirol UA-25EX to a Fireface UC. The reason for my update was that,
the Edirol only had one out, which ment that if i was recording, i had to turn of my monitors while using headphones.
Needles to say this was rather annoying.

After researching a lot, i decided that RME was what i was going for as it have a good renome within the comunity.
Since i really liked the idea about the ARC, i bought one of those to. After making my first recording it became evident
that this was a major update in regards to sound quality. Now i actually record, exactly what i hear thruogh the guitar amp!

Latencys were less than half(more like 1/4) of what i had with the Edirol. With a Fireface UC buffer size of 64 samples i
get an input latency of 1.90ms and output latency of 2.47ms! Audio roundtrip is 5.99ms/264 samples and Instrument is 3.92ms/173 samples.
All of these times is what my DAW(Studio one 4.6) is reporting in the options dialog. If i was using the same buffer size
settings with the Edirol, it would pop and crack like a popcorn machine. I dont use many tracks(4-10) and not a lot of VSTs,
and so far it has not complaint once with these settings.

Now to the annoying stuff about Fireface UC and ARC usb, and there is a few things.

The DC socket on the FF UC is very loose as reported here https://forum.rme-audio.de/viewtopic.php?id=27820 this is not so much an issue for me, as it is a permanent setup, it is concerning though. Most of my guitar pedals(if not all) are more tight than this. I don't get why this has not been fixed yet, as it was reported in 2018! Feeding the cable thruogh the hook doesn't solve the problem. It is still loose. As a company selling high-end products, RME should have worked on a fix with the innitital report.

The ARC usb can not control the input gain of mic/preamp 1-2 on the FF UC. This is something that really annoys me. It was one of the reasons i bought the ARC usb, just to find out that it is not possible. Whats even more annoying is that RME does not make it clear what functions are supported by which interfaces. The manual only says "..Some commands are not available at certain interfaces, or slightly changed due to different functionality.." Why is this not clear on the website? I mean it can't be that hard to make a chart with the functions of the ARC usb listed vertically and the interfaces horizontally marking the functions supported.

The stickers that comes with ARC usb does not cover all the functions supported. And some are just blank.
Why not provide all the functions as stickers and then some blanks?

All in all i am still happy with my new interface, however i feel that some of these issues, could have been fixed/avoided.