Ended up taking out the top shelf where monitor sits, dropping monitor down to accessories shelf (still needed a book to boost it a bit higher, may add a second book).

so I use the mouse on the top shelf.

Also there is not the option of sliding the keyboard shelf more to the right or left (as some brands offer) since this shelf slide into slots to support it

I put a 27" monitor on the top shelf and it feels stable.

I love the hidden shelf

The top shelf has plenty of room for a monitor and leaves space for me to use it as a writing desk as well since my monitor is on the right and not in the middle

One note of caution: the picture clearly shows the monitor pole assembled thru the back of the top shelf but the instructions CLEARLY state that it must be attached to a desk.