Honestly can't believe how much of an upgrade this is. 15 years of the plastic sleeves and one machine that still has them has shown vastly different performance. About to snag one for the new pro because it's that good. Other upgrades I have tried weren't really upgrades compared to this.

Did you get the one from Coffee-sensor?

I got Stefano's stainless version. Fit perfect if a little more snug than plastic sleeve. So smooth to pull. I had been watching YouTubers lift that lever so fast and thinking my machine doesn't do that even with a freshly lubed and serviced group. Now I know. Lol.

Actually I was thinking of buying the brass version from coffee sensor for the new machine since I have a couple mods I plan on getting all at once. Figure it might have some thermal differences to the stainless. Will see if it matters with performance at all.

I was asking because Coffee-sensor's sleeves are designed to have the water inlet hole on the opposite side of the group and more efficiently use the cool water inside the group chamber.

I don't know about Stefano's although I'm sure they are well designed and a DEFINITE upgrade

Thanks for posting that. I had no idea they were that different. Makes sense though as coffee sensor are modders. Basically it will behave differently because of design. I like the idea though. Avoiding the heavy rush of water may be part of my routine but I would be good mostly sidestepping it and focusing on other things.

The Stefano's version looked just like the plastic sleeve so I put it in to line up same as the original. Lined up for the shower screen easy. It is not as loud and didn't really feel it thunk the lever like it will with the plastic. Wonder what that means inside the chamber.

Here is a weird one. Working on both machines a bit this week and got a stainless sleeve for the gen 3 pro. So the following photo is a view of the piston sleeve, no hole visible. This was factory set as I haven't touched the grouphead until last night. Is this the way they install now or is this just a QC oops? It explains some behavioural quirks of this machine. Namely the extra loud thunk and whack against the lever when water goes in. This sleeve is coming out anyway for the stainless so no big deal. Guess I will shoot an email to clarify the placement of the hole in the stainless.

A quick email exchange and the answer is the stainless steel piston insert should end up with the water inlet hole facing the front of the group not the boiler.

So same as the coffee sensor version placement wise.

Well it has been fifteen years since I swapped out my first plastic sleeve on that machine so that episode is lost to time. Lol. Quick little change though for the Stradivari at least. I was having a hard time popping the PF gasket out of the gen 3 though. Haven't had a reason to as it's only 7 months old. I remember the Stradivari being a major pain the first time too and easier since.