Given the choice...u joints

Non-servicable joints are usually used in race and XHD applications because they tend to be "solid" (not cross-drilled) and stronger but nothing wrong with them in all applications. I don't know if they might last longer wear-wize if you don't plan to ever grease them anyway.

A servicable/greasable u-joint with the fitting in the cap would be my choice over one with the fitting in the body. Reason being is that the grease fitting hole weakens the u-joint. If using one with a grease fitting in the body between the caps, it's best to install the joint with the grease fitting hole in compression in between the caps, as the load is applied from the trans to the driveshaft and pinion yoke. That way the torque isn't trying to spread the u-joint apart at its weakest location.