Failing autotopoff.com float switches

I bought several float switches from autotopoff.com back in late 2009 and they have worked reliably for years. Unfortunately two of them have had too much salt spray exposure over the years and needed replacement.

I bought two double float switches from autotopoff.com in January. One of them is being used for run-dry protection on my return pump, so it has electrical load 24-7 (just like the one it replaced). After a few days it failed, causing the pump to stop. I had not installed the second one yet.

I contacted autotopoff.com and they sent me a replacement and paid return shipping for the broken one. In the meantime though, I tested the second one and it also failed after several days of operation. Also, the replacement has now failed. I never installed these in my system and it took a while for me to realize this is happening. I just contacted them today.

I know others have been using their product without problems but has anybody ordered one lately for this use? Is anybody else experiencing problems?

I really don't know if I want another replacement from them, because this doesn't look like an isolated problem. Any suggestions?