As a general rule, digital is more consistent/"accurate".
Cheap/typical analog hygrometers invariably have poor performance. What do you expect from such an inexpensive, almost freebie type device?? Not two analog devices will ever perform the same.
The real problem is, relative humidity is notoriously difficult to measure, thus the "relative" bit, Ha!
Any instrument has a "sweet spot" in their range where they are most accurate.
Hygrometers show 0% - 100% and it is impossible for an analog instrument (of any kind) to have full scale accuracy like that. Digital units fare much better, but the rub is price/performance ratio with even lab rated instruments costing $$$ to still vary in their readings. Trying hard not to get too esoteric, but basically, IMO, you need to spend the money on a Western Caliber or better unit if you are concerned with accuracy. Once you have one reliable instrument you can use it as a gauge against the others. Some, as I, use those exclusively now and just forgettaboutit. Thankfully, for cigars, we are only concerned with a narrow range of ~60% - 75% so this isn't difficult to dial in.