I've got both and I think I've used them both in my show for 3 years (I can't remember if I used the SSR4 the first year). They both have their place and are fine pieces of equipment. Both of them have worked very reliably for me as well, no issues over the 3 years. You will occasionally see somebody report an issue with the SSR4, but normally it is related to power. They can be a little sensitive to power issues if you don't have good power to them, say they are daisy chained at the end of a long extension cord or there is a bunch of equipment on the circuit. Not really a problem, it's just that RJ fit so much in the SSR4 that they are sensitive to power fluctations.
I've been running two Freestyles for the last 3 years. They are very solid and I've never experienced any issues with them. That said, I am thinking about removing them from my display next year and using LE's in their place. It is mainly a convenience thing. The LE is just way more convenient with its channel readout, text function, DMX receive light, wireless links...... The list goes on for a while. Also, when you have a bunch of SSR's plugged into the FS you are talking a lot of cords. If you have a bunch of elements close together that use SSRs it isn't so bad, but you can quickly have a rats nest of cables.
I'm still undecided, but I might be moving away from the Freestyles. Again, no issue with reliability of functionality, just ease of use and features.
Hope that helps.
Ron