IMO the X1800 fx don’t sound worse than the Pioneers and it is very fun to play on in combination with the players.
People wanting to use the players as players and not controllers should very seriously consider one.
I don’t have any boutique analog rotaries, but the MP2015 is a little more open, smooth, refined, clear, and I guess transparent to the original data piped in. You’re not really buying the X1800
for reference boutique audiophile stuff though but for the effects and roll capability themselves, which work better talking with the SC5000s. While I’m not the best judge of effects sound quality (probably lack the reference effects baseline, only used a DB2 once), it’s all just software.
So whether it’s the overall sound quality or the effects coding, it should be possible for it to improve over time. Has your feelings about the X1800 continued to be positive?