You probably know already what to expect from an EBow, and it's exactly that; a simple tool for creating infinite, violin-like sustain on a guitar. It does that beautifully! I bought one to add drones and string-quartet-esque harmonies to my music, and in the process of doing this, I came to realise the EBow is a touch more versatile than you might expect. There's quite a few secrets to getting some really varied stuff out of it!
For one, the device has two modes; one encourages more natural sustain, simply extending the note you play, but there's another mode that encourages rich upper harmonics to come into play. Now that's where things can get REALLY crazy!
How the EBow reacts with the pickups on your guitar is also very interesting; I'm not sure what exactly sure what about the pickups that causes this variation, but I've noticed on my own SSS guitar that the sustain is very mellow and ambient with my middle pickup sat beneath it, and bring out much more of the rich overtones and feedback-like sounds over the neck PUP. This likely won't be the same for you, but my point is, experiment! It's also worth noting that you don't have to have the pickup you're using with the EBow selected for it to work; yet another piece of the puzzle to solve!
I have two very minor complaints; the first is that the EBow itself is made out of a very flimsy feeling plastic (though I'm quietly grateful for this, as it feels surprisingly weighty once you get a battery into it!). The second is more a cautionary note than a complaint, but I feel you should be aware that the EBow causes the string to vibrate really very aggressively, which will likely mean that you will find it quite a bit louder than you usually are on your current setup. Again, not exactly an issue, but if you're in a very grumpy-neighbour-intensive area, I'd lower the volume a tad!
All in all, however, the EBow has made a fine addition to my ambient arsenal; there aren't many options to get this kind of sound, and the EBow sells for loose change compared to a special pickup system, and is a bit more unique than the effects pedals that try and capture the sound. Recommended!