The Series 60 MIDP SDK 1.2.1 does the best job for testing. Any bug/exception that would occur on your 3650 also does on this SDK's emulator and vice-versa (at least, as far as I have seen when using this SDK). It looks like it emulates a Nokia 7650.
The Series 60 MIDP Concept SDK Beta 0.3.1, Nokia Edition works well too, but is generally too lenient and it emulates a MIDP2.0 device (it is backward compatible with MIDP1.0 midlets, but it is not nice to see something working on your emulator, but having it crash on your phone). Use this SDK/emulator when you want to test your app for newer phones, such as the 6600.