I’ve used both the OD1X and DS1X and they are both good albeit digital sounding pedals
I like that they have a bass control knob as these types of pedals can be a bit thin at times
I have a DS-1X (and an OD-1X). To be honest I don't play through it much because I tend to prefer fuzz but I certainly like it. I have an '81 to compare and had one probably manufactured about four or five years before SMD, maybe longer (not sure of the year any more); I sold it because the '81 is so good and made it redundant. The core tone is very much DS-1. It does sound a tad brighter compared to a DS-1 and some people may equate this to sounding digital but IMO not because it's more of a voicing thing. The Low control doesn't add too much bass so I tend run it with Low above 12 O'clock and High below 12 O'clock, exact settings depending on how fat the core amp tone is. It doesn't have the fizziness of a DS-1 and like the analog version sounds best through an amp on the edge of break-up. The tone controls do make for more versatility and like the DS-1 can make for a great OD tone that can push an amp into juicy sounding, sustaining tones.
I have to older DS1 and have never quite figured out how to best utilized it with my gainy Orange amp. I may just try it in the amp's loop for “ barely on”boost. Does any owner use the amp,loop for such a purpose? The amp has great gain on its own, but it would be an accomplishment if I get get that gain to sustain especially on the notes pup in the 12th - 15th fret territor.
I occasionally plug my DS-1 into either a OR15 or CR60. I haven't tried it in loop and put it in the front. I set the amp to edge-of-breakup and adjust the DS-1 until I get big fat, juicy, sustained singing tones. To my ears the DS-1 is a match made in heaven with my Orange amps. Works well for relatively low level volume home playing too.