Question about linear rails

[Saikedo]

Printer Model

Voron 2.4 (350x350x350

Hi, I ordered some linear rails from zyltech and the carriages that I receive look a bit different from what was shown on the website. I was wondering if anyone had any experience with these to see if there are any negative aspects for the ones that I received.

The website shows carriages that are made out of metal in the center and just have removable plastic cups at the end. What I receive also has plastic at the bottom corners. I am attaching a photo showing what was expected and what I received just in case that will be helpful.

Thank you.

 

[Saikedo]

Note, after disassembling the carriage, I can see now that balls actually roll through the plastic when they are inside. Is that bad? Will the rails perform as well as the full metal ones? This was supposed to be a mid-tier rail.

 

[120decibell]

The outer races take no load so they can be plastic without and performance impact.