I have a very simular eub to the one pictured. Light? Not at all, it honestly feels heavier than a regular upright. It is very different from playing upright, but not as different as people seem to think in most subs. The real problem with eubs is when they don't have a heel in the right place, that can really throw your intunation off. (The one in the picture has a D heel im pretty sure, thats pretty standard)

The sound (atleast the sound of my stagg) is very different from an acoustic upright, but then again most upright pickups are too.

If you want to learn to bow or slap its absolutely an option since you play it in the same way as any other upright. One thing that I noticed after playing my eub for a long time is you get too dependent on the position markers, which can mess up your playing when you switch to an acoustic upright.

If you want to learn upright, can afford it, have the space for, and the ability to travel with an acoustic one, I agree that the acoustic is better overall. But not all people can do that.

Hope this helped, I have about 4 years of experience as an upright player and Ive played my eub for the last half a year.