To be honest, I don't really have that much to say about the interface. It looks, feels and sounds pretty high-quality, performs well and if you're only looking to record vocals and one instrument at a time chances are you're going to enjoy this interface as much as I did for the longest time.
Two things I'd like to add, however, are that FIRSTLY, if you own headphones with an impendance >100 ohm, I would urge you to maybe look for other interfaces with an integrated amplifier, as the solo doesn't come with a potent enough headphone amp (at least not for my 250 ohm dt770 pros) and, SECONDLY, a problem I DID have with the interface after about a year of using it, is a certain crackle in my monitors when i turn the volume knob, coming from a buildup of dirt behind the volume knob itself. I've reported this to Focusrite and until now they've been very happy to help, I might even get a replacement free of charge because I still am eligible for one due to their warranty. I still felt like including this.
Overall though, pretty decent interface. Would recommend to anybody looking to buy their first or (as in my case) second audio interface. Does it's job very well with no limitations and compromises in audio quality.