My husband and I have had many enema bags over two decades, the conventional red type bought at different drugstores.
While they all worked well, they had to be discarded periodically because coffee stained them and they looked gross after a while. I decided to get this silicone bag because, in theory, silicone is an inert material, and therefore I would avoid whatever toxins the red ones may leach.
This one works great, it cleans easily, I do not anticipate it getting stained by coffee, because you can actually wash the main container with soap; I use a very mild soap.
The valve works really well, I have been careful, as some reviews say it breaks easily. But after about 6 uses, it has worked very well.

Only minor inconvenience, it that it stops draining when the liquid drains to half the length of the tube, which is about 50 ml. So, I am just making a little bit more coffee to compensate.

This is the best kit around. It has the valve to control flow which is IMPOSSIBLE to backflow. It had the choice of tips, in silicone (Which many favor) and plastic, which is good for those who only use silicone lubes which would melt the silicone ones.
The bag actually holds like 2 3/4 quarts if you fill it to the brim hanging on one hook on top. Hooked over the two tabs it holds about 2.5 quarts. I only use one hook, with the sturdy plastic covered "S" hook included, because I put my https://www.amazon.com/gp/product/B004WE73N2/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1 thermometer in the other eyelet to check the water temperature. Never go above 103 degrees Fahrenheit (39 C), it will burn you badly!! I've found below 96 degrees (35.5 C) I get bowel contractions and can't even get the whole bag in me before I have to jump on the toilet. This may vary for you.
I did buy the same tubing/valve replacement line for this to combine it with just the 4 quart bag from someone else. It doesn't have the three tips included in this kit. I don't like the included bag because it has "Enema" below the premium logo. not very discreet if your are on a trip and it's in your bag(s). I often do a "Double flush" ( 2 Full bags) on a trip, so i don't need to be looking for bathrooms as much or spending long time in them because I can go two full days poop free after a double flush.
I haven't used the 4 quart bag because I want to see if i can just do one huge "flush" instead of spending nearly 3 hours plus on a "double flush". If you have never done a 2 quart enema you need to wait at least another hour AFTER you think it all comes out (For me about 45 minutes) because you can have a "watery discharge event" that has almost no feeling to it till it pours out of you.
I can't think of anything need to do to this kit except a link to tip replacements and a spare/replacement hose on the kit page for ease of ordering. i know some folks go nuts with boiling and sterilizing their enema kits. As long as ONLY YOU use the kit cleaning/replacing the tip below the backflow valve. The bacteria in your OWN feces is unlikely to make you sick but it could make another sick. Your immune system is tuned to your particular flora.
Never, ever share a kit and especially a tip. Your flora might make another person dreadfully ill and their's to you. If you have more than one user get each their own kit and mark the bag and tubing with a letter/number for each person. I can't understand the boiling sterilizing thing but some folks are super freaked out by feces. Cleaning yourself and hands afterwards (Enema) are paramount so your bacteria doesn't get on surfaces to others but your are literally sticking this thing in your anus and flushing out a huge amount of feces. it doesn't need to surgical sterilized. Use regular tap water and it will not have anything bad in it. If you have your own well don't use untreated water!! It may be fine to drink but your stomach acid may kill off bugs that if absorbed by your intestine walls could make you ill, and maybe kill you.

Good product

I must be doing something wrong. If I get on my knees, shoulders to the floor, then I cannot hold the tip in and turn the valve at the same time. How does anyone manage this? I can do just fine standing up, since I can use both hands, but lying down or on my knees I just can't do it. The tip comes out, I can't get the valve to work since I can't see it - I'm hoping someone else chimes in with how they manage it. I think the hose is so long that the weight of it pulls out the tip. Any suggestions?

compared to what I could get at the local pharmacy its 100x better, really comfortable, the only thing is its hard to see the measuring numbers