The Orchestra instruments didn't really impress me that much. I got it right before buying the SSO but didn't have time to listen to it until after I was playing around with SSO. I was regretting my purchase until I found the engine. The presets are great and you can set up your own. Yes, it is just arpeggiated instruments but it is really cool sounding and very easy to use, unlike some of the other arps I've tried. It makes great pads for your other sounds and blends decently with everything else I use.
And? It you already have a bunch of similar stuff, you may never use it.
Edit: I should also mention one of the first orchestral libraries I bought years ago was Solid State Symphony - very fun to play, but definitely on the synth sounding side. At the time I was mostly doing pop music, so this didn't bother me. The Orchestra is made with the same guy who made Solid State Symphony. So fun to work with and sounds good for what it is, but I wouldn't look to it as your basic orchestra, if that makes sense.