Why not use both? I have had siphon break holes fail as well, get clogged with algae or salt creep. Redundancy is always a good policy. If you get the swiss made angle check valve it comes apart for cleaning, you can also use unions on each end to be able to take it over to the sink and scrub it clean. They make true union swing check valves as well. Both I use but prefer the swiss made angle check valves.