Last summer I replaced my Klystra KP-1 nozzle with a Delrin Enema Nozzle Economy #2 - White - 3/4" Diameter from Optimal Health. This has solved the problem I was having with hemorrhoids. I no longer get swollen hemorrhoids when taking even one enema. I also purchased a 1/4" to 5/16" Clear Quick Disconnect adapter and two 5/16 to 5/16" Male Clear Quick Disconnect adapters from SiliconeNozzles.com. This allows me to change nozzles while using my one-gallon silicone bag.
A few days ago I took a series of enemas starting with 2 quarts of plain water mixed with 1/3 cup of liquid castile soap. I could only hold it for about 5 minutes. I must say, the resulting expulsion was definitely a thorough cleansing though not at all unpleasant with no cramping. When trying a second plain water rinse, I found that the urge to expel kept me from taking any new water using my delrin nozzle. So I replaced the delrin nozzle with my Health & Yoga rubber open end 26 Fr rubber colon tube from Amazon. With the colon tube I could deliver 2 quarts of water with 2 teaspoons of salt high in my colon without an immediate urge to expel. I was able to hold it for some time - I forget how much time - and the resulting expulsion was fairly clear.
On this web site I see some discussion of cramps and urge to expel. These are two different aspects of enemas. I never get cramps; I'm not sure I'd enjoy enemas if I did. Resisting the urge to expel is one of the main attractions of enemas for me.