So I don’t see the Cool Plates on Bambu’s site. Did they stop making them?
I also don’t see an Engineering Plate on there site as well.
Do I really need these two plates or is having a Smooth PEI Plate, Textured PEI Plate, and a High Temperature Plate all I really need.
I print mainly PLA, PLA+, PLA Flex, TPU, and Carbon Fiber.
They have discontinued the cool plate but do have some stickers left otherise they sell PEI now
You don’t really need the Cool plate. The High Temperature plate is a smooth PEI replaceable sticker on one side that works without glue for PLA and most other materials that worked with the Cool plate, which usually required glue. The reverse side is the Engineering Plate.
Well, when printing PLA and having steep overhangs quite close to the plate, the lower temperature required for the Cool Plate makes a huge difference, even with the top of the X1C removed and the front door wide open. However, I have not tried using glue on the High Temperature or Smooth PEI Plates at the same low temperature – maybe this works fine as well. But this would require frequent tinkering with the filament settings or the usage of temporary stickers with the different optical code when using PEI as a „fake“ Cool Plate. And then the stickers for the Cool Plate are quite a bit cheaper than those for the High Temperature Plate. I rather expected them to discontinue this one as it is basically the same as the double-sided Smooth PEI Plate. 
Anyway, the replacement stickers are still available and I am ordering a bunch of those right now, just in case…
Mine came with a cool plate / engineering plate and they worked well. However, based on the experiences I’d had with a textured PIE bed, I bought an extra plate with my X1C and I almost always just use it.
The only issue I have with the PEI is that I need to keep the printer door open when printing PLA as with the higher bed temp, the chamber hets up a bit causing heat creep and blockages in the extruder. Not a big issue but probably why they included the cool plate originally.
I only return to the cool / engineering plates if I’m looking a smooth bottom surface.
Hi, I am new to most of this. Is the “replaceable sticker” the plate than came in the box, together with my X1 printer? Got my printer right before Christmas, have just started testing it. It came with a cool plate.
If I understand you correct, I can use this as a PEI plate?
I have big problems with large flat thin (4mm) rectangular models, because they part from the brim and start bending upwards.
Perhaps this new plate will help.
The type of sticker is printed on the sticker. If you received the Cool/Engineering plate, it is probably a replacement Cool sticker.