Hi, what are the pros and cons of the different ways of connecting the

Hi, what are the pros and cons of the different ways of connecting the t-slots? I’ve been looking at gussets, tapping the ends and 3d-printed braces. I’m looking for accuracy in getting them square. Are any of the above adjustable or do you have to get it spot-on with the install?
Also, for driving the XY axes is there any downside to direct-drive through a shaft coupler as opposed to belt-driven?
Thanks!

Gussets are more expensive than the angle brackets, but it seems they can give you a more rigid machine.

I really don’t know if direct coupler or belt is better. Belts let me put the motor where I want it, direct drive means motors sticking out the machine’s side. But if you’re enclosing, that keeps the motor out of the enclosure heat.