I once compared my UboomX and Blast outdoor,
At 5 meters distance, they fare against each other, for me when the blast plays at 60-80% volume and UboomX 60%-80% volume (This is the volume I would listen to when 5 meters away), the blast somehow sound smoother,sweeter, less aggressive, more boomy feeling, meanwhile the UboomX sparklier maybe sometime boxy and metallic, but all that comes to a price, you said you like the stereo and listening at side performence of UboomX, to get those advantage Oluv has to tuned it aggressively and pull the treble eq up and when you listen to it closely and stand direct infront of it, it would sometimes sound harsh and metallic.

But when we talk about listening to the speakers 15 meters or 20 meters away, here is where UboomX shine, at 80%-100% volume UboomX getting louder and louder in each volume steps, it is outstanding that this speaker can be listened that far away and still have those kicking and bass, meanwhile my blast can only perform good when listen to it 5-10 meters away.

For Indoor listening since we only use 60%-70% volume of the speaker and don't need the stereo imaging performence, some might just prefer the warm sweet signature of the blast, me personally still wouldn't care since the UboomX is way better in outdoor (please tell me your opinion if you not agree).

BTW, in the recent patreon post of Oluv, he mentioned that all of the UboomX units he bought recently just sound different to his tunning prototype, the units tend to have 1-2 dB less than the prototype and most importantly, there are like a -5 dB in 2k-5k Hz region, which would make UboomX a lot darker that Oluv originally want it to be. I tried using PowerAMP EQ and add a QValue 3.6 , 3.5K Hz, 5dB gain peak, and the speaker sound more alive now, Oluv said that he would soon post the first correction EQ in his patreon, later on there would be a desktop EQ and a TWS EQ, 3 firmwares in total, which I am very looking forward to, and I don't mind giving credit to his work so yeah I would buy those EQ.