The 2352 has one SSR output and one dry contact for an output (Not an SSR). It's control algorithms are different.
The 2352 has an auto tune function for PID controls opposed to the 2362's manual configuration. The 2352 also has a much shorter duty cycle setting than the 2362.
For HERMS, BK, and fridge controls the 2362 is fine when used in limit mode. For RIMS applications I would rather have the advanced PID equations used in the 2352. There are also other differences but those are the most significant.
Ok, so I have read the two manuals side-by-side and have tried to make sense of the differences. Much of what CodeRage said is correct, although both
do have Auto Tune, which is a big deal in my book.
The 2362 is nearly the same as the TET612 I'm about to replace, but with some significant software upgrades. The biggest are the on/off control, manual mode, and limit mode, which acts like a latching relay to shutdown the SSR in case of runaway temps. They advertise the 2362 as being ideal for refrigeration because of the on/off mode, but the built-in relays are only rated for 3A at 240V (they don't give a 120V rating, but I'd guess 5A).
The only thing the 2352 seems to lack as compared to the 2362 is the limit mode. I wonder how useful this really is in practice, though. With limit mode on the 2362, when the limit temp is reached, the power is disconnected and must be reset manually. It's a good safety feature against dry fire I suppose, but your temp sensors would have to be placed in exactly the right spot to be able to detect that condition (i.e., inside a RIMS chamber). Mine aren't.
The 2352 seems superior in every other respect. Its internal relays are rated for 7A @ 240V (10A @ 120V).
(This is wrong. I misread the manual.) It has fuzzy logic enhanced PID control, which presumably results in more accurate and smoother predictions and control which is ideal for RIMS. It also has manual control, as well as dual stage on/off, so if you want to control a refigerator with it, for $45 this controller does the same thing as a dual stage Love controller.
(Also incorrect. For high current relay switching, look at the 2342.) Also, and I don't know if this matters to us (but I don't doubt someone here might find a way to exploit it

), the 2352 allows for voltage and current sensor inputs in addition to thermocouples and RTDs (don't pressure sensors send voltage?)
Those were the big things that jumped out at me. For my money, I'd rather spend the extra $3 and get a controller that can be used for just about anything I can possibly think of (and some I can't). In fact, I'm thinking now that I might just replace both of my TET612's, not just the one giving me trouble. The only thing that really sux about that is that I'll have to rewire my CP due to the different pin layouts...
I hope this helps...
MrH