But that is a 4 Channel DS1000Z Series, the 2 Channel DS1202Z-E 200MHz has a different front end. It is not comparable and also not comparable to the one that IMSAI guy has.
I posted the step response on my Rigol DS1000Z hacked to 100MHz.
If you truly need 200MHz, the DS1000Z is probably not for you.
But, I will give up bandwidth for four channels any day.
How much are you willing to spend? Have you looked at the Rigol DS5000 Series.
I believe Dave did a video and there is a thread about hacking it.
Don't know if it's been hacked yet or not.
The IMSAI guy has a DS1074Z scope (i.e. the exact scope I have).
We both hacked them to 100MHz bandwidth.
Both his video and my step response are with only one channel ON (i.e. the 1GS/s).
The 2 Channel DS1202Z-E would be comparable to the DS2000 series scope you got rid of.
The only reason I posted the IMSAI video and my step response is because you mentioned in your first post that you considered a DS1054Z.
I'm just giving you some comparison information to the Siglent scopes, which for 200MHz, cost twice as much.
Or for a little more than the Siglent's, the Rigol DS5000 series with possible (?) hack to 300MHz.