Oh yeah, definitely. But I love the 20IR too and it is just one of those el84 versus 6l6 things. The 20IR sounds better to me than other el84 amps i've owned and can do metal and chugging riffs. It just doesn't do the 6l6 level of chug.
I always struggle to explain what I hear with el84 amps compared with 6l6. It is more "crisp", less lows, not as tight, etc. It still sounds great and like I said, i'm a fan of the 20IR. One of these days I should do some sort of comparison clip.
I don't think anyone would feel let down with a 20IR. It is a great amp. Once you plug into the Syn-2 with a bigger power amp though it opens up and just feels bigger. Even thru my Orange 1x12, a lot of that boxy sound disappears and sounds huge.