On The Other Hand: The OP seems to be asking if he can hack his Siglent the same way that happy Rigol owners are busy hacking theirs. A quick google search will tell you that the answer to that question is "no".
This is true. I have not (yet) seen any evidence for Siglent SDS1000X/X+ or SDS2000X this kind of hack what is at this time available for Rigol 1000Z and 2000 models. No one also know how long Rigol continue this marketing trick.
Only what Siglent offer at this time is limited time offer for SDS2000X series so that when pay 70MHz model price then get 100MHz model, when pay 100MHz model price, get 200MHz model etc. And other offer is for options.
But for exaple, in standard you get with SDS2000X
max 140000wfm/s
max 140M memory (in 4 channel models 2 x 140M) (+ some extra memory for History buffer and Sequence acquisition.)
! max 80000 waveform history buffer (always working backside with current speed (exept if Sequence acquisition is in use). "Stop and look history" feature)
max 80000 waveform (segment) in Sequence mode
! max 500000 wfm/s speed in Sequence mode inside one Sequence.
! Full speed hardware based mask test (up to 140000wfm/s independdent of test result)
Hardware ready for MSO with 16 channel digital inputs (MSO functions activation need license and using need also 16 channel LA probe)
Hardware ready 1Ch 25MHz AWG (activation need license)
What is best for individual user depends individual needs and what things/features user give more or less weight.