I just did my first "SSE" in quite a while tonight and in fact I'm expelling what might be the last round of it as I write this, since I seem to have some time on my hands. It was 3.5 quarts (2.5 q rubber bag) of saline plus 1 TBSP of Bronner-like (Dr. Woods) Castile soap per quart. There were so many fun parts to it, but the getting up from the bathroom rug twice to refill and later expel were memorable. Lots of pleasant gurgling, essentially no cramps, and a long (but very distended, even on my back) comfortable retention. I think I tried more soap than that once, perhaps 1.5 TBSP/q, but got too much cramping for my liking. This is a good recipe for regular non-adventurous enemas. If I want more gurgling, I'll add a small %'ge of glycerin.
I've got a colonoscopy coming up in a month or two, so it'll be fun to do a couple of big clean outs to add some amusement to the oral prep stuff. I hope it's different than last time in 2010, (same doc) because that was the worst thing I've ever put in my mouth, let alone swallowed.