I use boris for this. Another great transition is to reverse the particle explosion - particles come together into the letters. I owuld assume the other programs also have this capability (if nothing else use the velocity envelopes in Vegas to create the reverse effect). Cheezy but great!!
You could always get Particle illusion SE, which sells for $99 and is the same particle generator used in Combustion 3. It's an EXCELLENT particle generator, hollywood quality....
Satiish plugins are great, especially the shatter. But Blufftitler text is better and has better particle generatorsl Plus has a large number of examples. it's easy to add to, I have added addtional reflective surfaces for textsurfaces. Blufftitler is alot easier and faster than AE, but does have limitations, ie. limited output formats,frameserving, but of course, it's only $45 vs. $399.