Just got an ET-733 today. This will be my third Maverick. First was a long departed single probe model. Then I upgraded to the ET-732 several years ago when the buttons on the single probe stopped working. The 732 has been great except for one fatal flaw: setting the temp alarms is a royal PITA, having to hold the button while it scrolls all the way to 600 degrees, starts over at 50 degrees and goes up again. I always miss my target and have to do it a second time. Make it a complete hassle to change the alarms, like if I want to tighten up the grill temp range after stabilizing the smoker. Or change to a different food temp.
The 733 solves this problem with up and down buttons for temp alarm settings.
So anyway, I now have a 732 and a 733 with six probes that will work with either of them -- two short BBQ probes, one curved food probe, and three straight hybrid probes. A couple of things that I suspected, but have confirmed.
1) The transmitter units are identical. The 732 transmitter can be synched to the 733 receiver, and vice versa.
2) You can sync BOTH receivers to the same transmitter. Just turn on both receivers, then turn on the transmitter, and the same temps are displayed on both receivers.
This is very cool as Murphy's law for me means that I have always left the receiver in a different room when I want to check the grill temp. For two probes monitoring grill temps, I can now have a display in two rooms -- one next to the computer or the TV and one in the kitchen or out by the grill. When it's time to put probes in the food. Just turn off one receiver and link it up to a second transmitter for monitoring two grill temps AND two food temps. Or just leave everything synced, move the probes to the food, and monitor food temps in two places.
What I'll probably end up doing is leaving the 732 set for alarms on smoker temps for two probes and use that when I'm doing a smoke, adding the 733 for food. Then, since it's easy to switch around, use the 733 for everyday Weber kettle roasting where a single grate temp and a single food temp is all you need (like an indirect pork roast or chicken breasts).
Anyway, just thought I would pass along that these two models can be mixed and matched in every imaginable way: probes, transmitters, and receivers...