@wisty
Congratulations with the ElectronSE. I too had a pair of Double Impacts (upgrade version and with grills and spikes) - they were outstanding.
I also have GoldenEar Triton 3+, and Martin Logan e-stats, but the nail in the coffin for the DI's was the set of LXmini's I DIY'd just over a year ago. Side-by-side, LXmini's sound like you're there, and all the rest sound like 'speakers' next to them. LXmini's are a hassle (DIY, DSP crossover and multiple amp channels) and need subs (prefer stereo pair) to match bass of DI's. I did use the DI's as a benchmark to change the voicing of the LXmini's to better match the upper extension before I sold them.
The DI's are advertised as 'ultra-linear' freq. response, specifically ±1dB 70 - 20kHz, and ±3dB 20 - 30kHz. But I don't find the ±1dB freq. response of the ElectronSE, just ±3dB 20 - 30kHz, which leaves one to assume they aren't ±1dB 70 - 20kHz.
The ElectronsSE's interest me, as part of a great 'budget' solution (which I think of occasionally to reboot/downsize my 2-ch system). Thinking a simple
economical option could be NAD M10 or M33 and the ElectronSE's. No fuss, great-sounding, unobtrusive system with Dirac room correction - add phono as necessary. Another good solution would be Spatial M3 Saphires for open-baffle goodness - if one had the space to put them out in the room (same issue as LX521.4).
That's what I'd do if I weren't chasing down the rabbit hole of omnidirectional, cardioid response, infinite transmission line, DSP crossovers, multi-channel DACs, multi-channel amps, and open-baffle subs.
ElectronSE's are on my short list, and (w/exception of GoldenEar), are the only 'box' speakers in my budget range that I'd consider.
Good choice - enjoy!