John Guest Speedfit vs other brands

[DITB]

I have speedfit on my cat, although I can't rule out that there are some other brands mixed in that I haven't seen yet. It's all in 15mm red and blue hoses (well, most of it). I want to add some non-return valves as well as stop valves here and there.

Can I add in other brands, or should I stick to John Guest Speedfit?

Transom water hose - has hot and cold, which is nice, however, it's routed such that if I open both hot and cold, and a cold tap is open inside, it will route hot water through the transom shower, into the cold tap! This for instance if the valves are on but the push-button on the shower-head isn't pressed. That is where I want to install non-return valves.

The cold water doesn't have many shut-off valves, so I want to add some. Fixing my watermaker at the moment, I can't switch the fresh water supply off without depressurising the whole water system. Also, in case of any leak, it is really useful to be able to isolate the leak.

Since my local shop (West M) doesn't seem to have JG Speedfit, I was considering if I could use the Whale quick connect parts ...

[sestina]

I reckon the Whale fittings are the same as JG Speedfit. Any metric fittings (brass or plastic) will work as they are based on a nominal outside diameter of 15mm. Though it is a good idea to use the support sleeves especially when using brass compression fittings.

Get anything you want from https://www.bes.co.uk/index.asp

[Jsta_Rebel]

The only difference between JG and other brands of speedfit fittings is that the locking ring inside the JG fitting is stainless, and in some other less expensive brands I've seen, it's plastic. The plastic does not hole near as good as the stainless "gripper" locking ring. Pull one apart and have a looksy.