I've already completed one song using the software. Last night I began on another one where I expect to have about 20 tracks to complete the song. I'm on track 3 now.

The reverbs are amazing. The reverb timing length is great. Although the reverb was created by Presonus, it very much reminds me of Lexicon verbs. The professional version has SO many options it's insane. The workflow, drag & drop, project, Studio Live, Melodyne, all the plug-ins, and other included effects make the software a one all be all (at least for me). It's so nice that you can create and save effects and import the same effects into new projects. I'm sure you two probably use more than one keyboard...I've discovered while one will suffice but two or three can make your writing & playing more functional. While writing & recording last night I realized life would be much easier if I would get another.
To mgriffin, if you'd like, perhaps we could make this post a place to converse about our experiences with Studio One once you get your full version? The effects in the software is extremely fun to mess with. It's turning me into a nerd. ;-) haha.