I'm going to say that the ELA won't be very stable sitting on its button, considering it appears to share the same button as a PrecisePlus.
That's the only thing holding me back from ordering right now. Most of the pictures I've seen are showing them laying on their side. I've got to have something that is relatively stable standing upright. I would be carrying it to different places through out the house and I can't take some sort of holder along with me to put it in all the time. If I still used carto tanks that wouldn't be much of a problem but these mesh rbas have to be kept upright or they will leak.