Has anyone figured out the differences between the T1 2.1 and 2.5?

I'm planning on building an itx pc in a T1 sandwich case with a 3080 ti and 7800x3d however I'm still uncertain as to which T1 I should buy. I've looked for a definite answer but there doesn't seem to be anyone who has both models and made a comparison. So does anyone know if they're basically identical or if there is that much of a quality difference favoring the T1 2.1 over the 2.5?
In addition, is the CNC aluminium that big of a difference form the regular aluminium? Also, if you can recommend an air cooler for the 7800x3d for this case that'd be great.Thank you for your help!