It came down to a photo-finish (pun intended) between 22 Slides and Squarespace. I went with 22 Slides mainly because I like the fact that I can insert text in between photos in a horizontal-sliding gallery. And 22 Slides is a little cheaper. But I could change my mind later. I like Squarespace a lot too.
One significant difference: Squarespace provides its own blog platform, and 22 Slides connects to Tumblr. I never quite made my mind up about Tumblr. I fear that I’m too old to be on Tumblr. The other problem with Tumblr (well, potential problem) is that it’s designed for short posts and I’m long-winded.
But I’ve used Tumblr now and then over the years. It is pretty easy to use, handles photos tolerably well. And it’s what 22 Slides supports. End of story.