Neptune is coming out with a new float switch it looks really good.
the tunze is better then just the neptune float switches they have going on right now
I buy my float switches directly from tunze spare parts shop online and use their magnet holders. I have two in the sump and one upside down in the ATO container. I 2 in the sump are for high water safety (ATO off) and lower switch turns ATO on and off. Switch in the sump turns ATO off when water level gets too low and sends me a text / email to refill the ATO container. When using Kalk in the ATO I also have a safe ATO to turn off if PH gets too high. So for me, I'd rather use this setup with the Apex. More flexibility and the only difference is I removed the tunze brain.