Yeah it's amazing how different the two converters sound. Especially on percussive sources. I use an re20 and it's a pretty percussive mic. On the apollo it was a soft punch that ( in my opinion ) sounds soft. No matter how aggressive I got with compression or adding eq, it would remain human like. The symphony ( mk 1 ) has this jolt in the lower midrange that is sometimes ridiculous on kick drum. I find myself playing the mic all the way towards the batter to chill out the air blast. It's rather intense.
On everything else ( vocals, guitar, bass ) it sounds amazingly life like and full. And i'm sure over a lot of tracks, it will be great as well. I'm at a crossroads personally. I don't miss anything about the ua plugins. But I miss the ease of the software and the sound sometimes. I had the silver box & I like the way the black box sounds.
If the apollo twin had optical out, I could satisfy my need for the kick drum with two channels of ua conversion. lol
But yeah, the symphony gets expensive. Personally, I noticed a huge difference in clarity with the apollo when I borrowed my friends MK3 clock. Because of it, I almost didn't buy the symphony. I'm rambling now so I'll stop. lol