They are both toys for beginners, get a KORG PA1000 and that will cover everything for you up to a pro level,
The are both in the same league of the PA1000. So this too is a toy for beginners (according to your reasoning, I do not agree with).
The truth is that if you blindly listen to a Sx700 and a Genos you cannot probably tell the difference. Let alone the casual listeners that do not even know what an arranger is and what are the companies that manufacture them.
What everybody for sure can tell the difference is when a pro plays a 20 years old keyboard and a beginner plays a, let's say, Genos.
Everybody will tell you that the 20 years old arranger sounds MUCH better!! Because it is the player that makes the difference. Never the tool.