Have both scopes, the Siglent is better for tighter low noise power measurments, bigger screen. The Rigol just has more horsepower, small screen, but I like it's gui and its felxibility & apps. Both are good scopes, and deliver a lot of bang per buck as you chaps across the pond say. The digital logic channels are useful tool.
Recently I've gone all Lecroy in the lab, still run both Rigol & Siglent in home labs both on the audio side.
If you wish for more information do PM
Sighound
That's a bit brief.
Boot time ?
Fan noise ?
Memory/sampling management ?
Which maintains best sampling rate/mem depth with all channels active ?
Yes it was a bit brief as I was about to go out TT, but I'm not a salesman here

I've owned the Rigol 8000 longer than the Siglent SDS6000, yes the Siglent has a less noisy fan and yes the Siglent has better sample per amount of channels active. However, its very rare I use more than two channels for those scopes.
You have to appreciate that not everything on EEV revolves around Siglent TT, I do like the brand and believe they have made good progress with the ability to compete with in T&E market well. However, like Guinness it’s not a one size fits all product other people will prefer other products its human nature. If there was no 'hacking' of T&E equipment many brands would not be in the position they are now pure and simple
Recently I've been debating whether to purchase the new Siglent SSA5000 analyser with the big 26.5Ghz BW its great looking package with decent features and the price is well trying to compete more with the mian stream guys which is fair as they have stepped up a gear or two. However, the phase noise is 105dbc/Hz, the RSA 5065 is 108dbc/hz already and has a hdmi output so I plumped for a quality used R&S FSV with a host of quality upgrades & upgraded clock option and warranty for very close cost to the 26Ghz Siglent version. Other will feel different
If I were using more channels, I would be using the Lecroy pure and simple or wishing to look seriously in depth at signals that we work with.
Nctnico & 2N3055 have a very valid point with probes, I've mentioned this before when purchasing ANY scope look at what you are using it for it and which probes are BEST suit to those applications.
My suggestions would be the following a quality HVDP/1Ma resolution quality current probe/Dedicated rail probe/Quality passive probes/ a couple of 1Ghz (min) Differential probe/Co-ax transmission line probe/active probes min 500Mhz/factory 75 Ohm adapters/differential common mode probe. I do have optically isolated probes as well for smps accurate high side measurements.
These items tend get over looked when purchasing any scope, so please do bear this in mind when looking at a new scope purchase.
I did a tot up of all of the Lecroy probes I have for the personal lab, they come to more than the cost of a fully loaded Wavepro HD so do your research and look at what you REALLY require not just what is desirable.
Sighound