Doesn't need more water than anything else, though need to be watered first year untill established.
Depending on your zone (6a and lower) may have a substantial dieback in a winter.
Cultivar is not stable enough to be left unattended, constantly producing solid green shoots which need to be removed.
Flowers is nothing to write home about and got lost among variegated foliage. Overall it may be called a foliage plant, not a flowering shrub.
On a scale of 1 to 5 I'd be willing to give 3.5 the most.

I bought one this spring just like you: had to wander around and find a spot for it. It was a three gallon pot and a beautiful full shape. Love at first sight, despite the fact that I usually don't like abelias.
Anyway, it has wilted a good bit in the heat of our days (mid to high 90s), but I rarely gave it any extra water and it perked up by morning each day. The color in the foliage (why I bought it) has held up as well as, maybe somewhat better than, most chartreuse plants in my zone. So far, so good. The research I did on it after I bought it says it will stay smaller and not get whippey. If so, I will be declaring it a winner. Am looking forward to seeing it do its autumn thing.

Thanks you guys! Very good information. The ones at Home Depot look like they're about ready to do their fall thing. :)

I bought 2 of them this past spring from Home Depot. They are in 3 gal. pots. I have a bed that needs reworking, but I couldn't do it in the spring and it is too hot now. So, the abelias have sat on my covered patio all summer. Hopefully, they are not getting rootbound. I bought them for their foliage color. So far, I haven't had any green shoots and while the flowers aren't spectacular, I have been surprised by the fact that they have been blooming for several months. Unless they behave differently once they are put in the ground, I have been very pleased with them.