I’ve been looking at Selection boxes recently, and I’m not too sure how much this will affect performance on the clients.
“SelectionBox is an object which renders a 3D box around its Adornee when it is a descendant of the Workspace or anywhere where GUI objects are rendered. The box’s geometry consists of rectangular prisms forming an outline/wireframe in addition to a surface for each of its faces. By default, only the outline is visible.”
Based on this I’m certain that it will affect something, as it’s render-based, just not sure how much.
I would appreciate if someone who knows more about them can answer.