Splinters
Yes a very take it slow process for those without a CNC, even then too much feed combined with the open sections its a high risk of breakage for sure.
I have a 3mm collet that fits my trimmer and its a chuck for the dremel.
I think the bit count for the panels was about one per panel.


Pottzy
I didn't have any Wests available or I would have agreed, and done it
The abrasive brush is a 3M product called Roloc and comes in various impregnated grades colour coded
 So yes it sands the wood. Great for ornate picture frames and the likes

The flex drive is a King Arthurs product
A pneumatic sanding system that holds the abrasive by pressure rather than glue



Regards Rob