Most of the time I will be using 2x Channels and the SDS1104X-E has 2 ADC's so will be 2x 1GSa which is the same as the DS2000 (I hope I've got this right) I found the DS2000 to be slow to use and a bit noisy looking at small signals and from what I have seen the Siglent models are better in this department, also there is no 4 channel DS2000 and the DS4000 range has been discontinued.
When I need to use 4 channels the bandwidth is not high, so the SDS1104X-E should be fine I hope, examples where I need 4 channels are: Multiple power rails and DC-DC, Primary and secondary sides to SMPSU's or other topologies, looking at "Dead time", this is often where I run out of channels quickly and need to look at multiple parts of a circuit/psu while watching dead time. So 4 channels would really help here.
Also audio/AF in and outs.
Use case for me is very broadbanded, electronic and electrical repair, circuit design, amateur/commercial radio such as repair and also design, serial uarts, playing with uC's, mainly the lower end STM32's. I'm really used to having up to 200MHz and would like that again.
Also this is a birthday present and I've been nagged what do I want as I'm difficult to buy for and she suggested a new "sillyscope" as she puts it.
I sold my DS2074 (200MHz Hack) And am really missing having a DSO.
I'm about to order the Siglent SDS1104-XE as I REALLY want a 4 channel scope this time and plan to "Liberate it for 200MHz" as I need at least 200MHz bandwidth.
And you don't consider you're down grading going to a SDS1104/1204X-E ?
You had 2 GSa/s and 56 Mpts and 8" display whereas SDS1000X-E series cannot offer any of that.
I did consider the Rigol DS1054Z but it seems like a big downgrade compared to the Rigol DS2074 I sold, I was really tempted to get it to gain the extra 2 channels but the bandwidth is just not enough even with all the "hacks"
Yes again that will be an even bigger downgrade.
Your DS2000 offered 5x sampling rate @ 200 MHz with both channels active whereas SDS1000X-E can only offer 2.5 the sampling required @200 MHz with all channels active.
Yes BW is a bitch as you must have sufficient sampling to match it and particularly as you're wanting to push past rated BW which will risk aliasing so IMO you will be better served with a DSO with 2 GSa/s sampling.
SDS2104X Plus can easily do this as despite its rated BW being just 100 MHz we have tested its -3dB point as ~185 MHz and as you're into hacking 350 MHz on all 4 channels can be achieved and 500 MHz on 2 channels if you push it right to the limit. There are reports of ~600 MHz BW for the 500 MHz option which still provides 3x+ sampling for the two 2GSa/s ADC's.
Take a moment to think more deeply about DSO selection.