Well @raysmtb1, many have been there but won’t want to admit it. A famous US manufacturer of DACs said something similar to you that DACS have more often minor differences (to paraphrase) but the better route is to invest in amplification. That’s been my experience but not with a long line of DACs to offer comparison. A long line of listening to varied (mostly tube) amplifiers over years, yes.
Most know the tech options although there’s an emerging vein with DSD upsampling with PS Audio and Cen Grand DSDDAC plus other big boys like Playback Design. (Had one of the original top Sony SACD players back in the day too.)
Then there’s the software upsampling with HQPlayer being really powerful plus the internal options built in Roon and Audirvana. With Audirvana Studio in my system, the upsampling option is quite nice up to 256 YMMV.
The AKM chips fancy upsampling to one bit DSD, outputs to a lovely bluish light display on an RME ADI-2. Many have experienced that upside with Holo DACs, Harmony, etc. and note HQPlayer elevates them to a significantly better sound.
Unsure on what you have tested but I’d love to hear a DSD upsampling shoot out between the RME ADI-2 FS, the Holo May and the Harmony. That would be fun.
(One additional note on the RME ADI-2 FS. When playing DSD Direct you need an external preamp to control the volume as volume control is lost when you make the DSD Direct setting. Found there was a benefit that way for the RME not doing that double duty in my system too. Completely different capability all around.)