What about the comparison between M11 Pro and DX220 ? Specifically M11 Pro's 4.4 mm output vs the DX228
DX228 has a fuller richer sound. M11pro has a slightly brighter sound. Both players have similar extension. Both players are good, but I prefer the DX228.
As for response, the M11pro is slightly faster, but not so much more that it is a deal breaker. I do like it for having the three inputs, and it is lighter and a tad smaller.
I tend to use both players on a day to day basis, more so than my other portables. I usually go for the DX229, unless I'm using earphones without a 4.4 plug (and without a handy adapter).
I use the Neutron music player on both players. To my ears it just sounds better, and it is certainly easy enough to use.
Also, it should be mentioned, that Amazon HD music doesn't play on the M11pro, unless one starts up a high resolution file with another player.
The DX228 has no issues with playing Amazon music.
On the other hand, the DX228 goes through battery juice like a drunken sailor on shore leave. Not a problem for me as I use my player at work, at a desk, with access to USB power.
Really, both players are TOTL players from their respective manufacturers. To me, the DX228 is one level above the M11pro, but it's not night and day, and the difference is small. The M11Pro is a bargain for it's going price, but it can be argued that same can be said of the more expensive DX228,
... and NO, I have no problems with response time and sluggishness with either player.