Planting Acer Palmatum near Sycamore

Can it be done? Next door neighbour has a mature Sycamore in their front garden and I want to plant an Acer my side, a few feet away. The Sycamore has already seen off a couple of Rhododendrons but my Camellia is doing okay.

Is it worth risking if I give the Acer plenty of supplemental watering, or is it a big no-no?

 

I would say "no". Sycamore is a greedy thug, nothing else likely to grow nearby.