There is no right or wrong. Folks with very traditional/heavily trimmed cabinetry may favor a panel match. Sometimes in a very modern kitchen, an integrated look /very sleek and flat paneled is favored - you can't even "find" the fridge. For the most part.......... it's let it shine. I assume you are referring to a sub zero or similar in your instance, and still a built in look, since it is adjacent to a doorway, thus allowing only the front of the fridge to be seen. If you want the sole focal point to be the 48 inch range.......it's certainly perfectly fine to match your shaker and panel it to blend in. Just make certain you allow for full extension door swings well prior to finalizing in any scenario, and make sure cabinet maker has specs for your fridge selection to ensure that.