David,
Our experience with Siglent has been just the opposite, and we were reluctant to acquire from them, but decided to get the SDS2000X+ DSO a few years ago. Out past history has been only to "trust" HP/AG/KS, Fluke and Tektronix, and a few others back then, so forking over our own $ now retired, was well a little risky. Now we have a number of Siglent instruments, DSOs, SA/VNA, AWGs, EL, PSs and a SDM3065X DMM.
All Siglent Instruments have performed well and continue to do so. The SDM3065X is "measured" against the old HP34401A, AG34401A, 3 KS34465As and a Keithley DMM6500. It's a good value, but not a substitute performance-wise for the other mentioned DMMs. Probably the best value overall "new" DMM in this upper end category tho, IMO.
Of course YMMV,
Best,