I own the Jotunheim 2 with the revised cleaner internal DAC. I owned the original JDS Element years ago, back when its DAC was USB adaptive mode. Both are well made with great sound and plenty of power. I didn't own them at the same time, and both are well engineered neutral amps that drive almost any headphone, so that's all I can say about sonic comparisons. The old Element's DAC had occasional audio glitches, but that was likely due to USB adaptive mode which is no longer relevant as they are all async now.
Both well engineered, built with quality parts, well supported with good warranty. I preferred the Jotunheim due to having an internal power supply (no wall wart like the Element), fully balanced yet also with single ended inputs & outputs, both line level and headphone, making it more flexible, and the Alps RK24 volume knob.