Thank you for your answers!
Especially about different HW révisions.
Just a little about the purpose of the scope i'm looking for: to test pocket AB amps i wanna make for fun, check if power is clean also and do some fun with uart. Nothing professional, just a hobby fun.
In Siglent i appreciate features like 4 channels, 1GSa/s per group, pretty fast waveforms/s aaand FFT (which looks good after the reviews i've seen), slow on 1Mpts but it's 1Mpts, so noise is lower and more details. I say again, it's for audio freq & for "excited" AB chips (which could do 20MHz or 30MHz in theory if i screw the schematic).
Also for the other fun cases i've seen that with scope and some math you can check C, L and electronic components (but i have testers also). I wanna enjoy it in my 36.
So my fun budget is 500-600€, and i agree with Dave (from YouTube), that 1k will be overkill for my needs. Also, compared to "same" rigols siglent more sensitive.
Next about hacks: 100MHz is okey for me, i don't need 200MHz, also i don't need 16digit channels (just 4 analog) and don't need generator cause i can make my own (w/ scope) or buy any other brand. But i want 100MHz i'm paying for. So here we speak about the hack and the screenshot from the review.
Why the hek 100MHz have -1dB at 75MHz?.. i can't get in. 200MHz model is cool at 200MHz and you pay for 200MHz, but when you buy 100MHz you don't pay 50MHz scope or 75MHz scope. So if it's pure software crap, well, i will hack that FIR config and enjoy my 100MHz scope.
If the frontend is different and poor, well, i will enjoy nothing and lose factory calibration (seen these comments in topic) which was made for 100MHz scope.
So, did actual SDS1104X-E have poor front (or the other parts) compared to SDS1204X-E or it's just software "issues"? I've seen siglent folks in thread also, if they have no NDA, it could be good to know simple "no bruh, it's just software" or "yeah, don't even try to get real numbers with latest 1104 models at 80-90MHz".
Before i was targeting MSO5074, hacked, sure, to get 100MHz, but 8Gsa/s it's total overkill for me (again i'm agree w/ Dave).