IMO A LA engine is not designed for 1.6 rockers. Why use 1.6 rockers on a street strip engine? Why use 1.6 rockers on any LA engine? Put the cam in that provides the lift you want and leave the problems associated with 1.6 rockers to someone else.

Use 1.5 rockers and have a more stabil, reliable valve train. Otherwise you must use bandaids to cover up the problem and have wore out valve guides much faster.