Hey, Jeremy. I have the Vienna Pro Player (paid) and the free version of Vienna Ensemble. I don't have Vienna Ensemble Pro and am ashamed to admit I don't even know the purpose of Ensemble. I think it somehow manages various instances of Vienna, but I am not really clear about that.
Keeping in mind that while I am classically trained and love symphonic music, my use of orchestra is chiefly as sweetening in rock, folk, and country pop that I write. One rock group I produce does pretty epic rock opera stuff that I orchestrate for them. Given that, here are my thoughts on Vienna:
• The matrix system is, for me, much easier to use than Hollywood's model. I especially appreciate the consistency. If I switch from orchestral to chamber to solo, etc. there is no confusion about how to get a particular articulation, and, in most cases, I don't even have to edit the keyswitches. (We are talking about strings, but the same applies to winds. I can change from Triple Horn to Vienna Horn, or from Oboe D'Amour to French Oboe without even editing the sequence.)
• Vienna is much easier on memory and CPU, although if you load all the articulations of Dimension Strings in multiple instances, you will naturally see some significant memory use. (I run in 64-bit with 12 GBs RAM.)
• Vienna Orchestral Strings sound exactly like an orchestra to me. I find the chamber strings a little austere and don't use them often, but there is nothing wrong with them. The main failure I have had with Vienna is getting a string quartet to sound right using the Solo Strings; but that may be my fault as an arranger.
• The tuning anomalies in Hollywood really bother me sometimes because they are very apparent. It annoys me to hear the same sour note every time I press a key that is critical to the song. With Dimension Strings, you can keep the parts perfect or select a degree of humanization. I know people will say that errors are realistic. My answer is that errors are the reason God put erase and undo buttons on recorders.
• Some people fault VSL for not having 2nd Violins. I am mixed on that. I don't find Hollywood's second violins to sound different enough from 1st violins to matter; however, that does avoid the issue of phasing if the parts cross the same note or play a unison line. The question is whether that is enough of an issue to warrant all the extra memory for loading second violins. I go back and forth on that issue. I can cheat with Vienna by using Orchestral Violins for 1st violins and Dimension Strings for 2nd violins. I have also used chamber strings as 2nd violins. In a recent record, I used Orchestral Violins for both 1st and 2nd, but then pasted in a single line using Chamber as 2nds when the parts were in unison.
Maybe I am lazy, but Hollywood is a lot of work. I am a songwriter and am usually anxious to get the parts down, not spend hours trying to go through patches. For this reason, the VSL matrix works better for me.
No disrespect to Hollywood, though. It is a great product that I have put on records and will continue to use.
Sorry for the long post but this is the most interesting topic on the forum to me.