Thanks Bapu, that's a good idea to do an A/B test. I've read a lot of good things about how easy and useful SM4 is.........been on my radar for awhile.........but, I do have OTS's acoustic.

Indiginus has a different approch to strumming than most other libraries.
 
Most, including Orange Tree and Music Lab use a chord detection system where you hold down a chord on your keyboard and the software detects the chord and converts it to guitar voicing. Up and down strokes are then triggered either manually from dedicated "repeat" keys or by a strum sequencer.
 
In SM3 Indiginus assignes a user programmable chord to each of 12 notes. If you are strumming mannualy down strokes on one octave and upstrokes on another. Velocity layers switch between sustained and muted strums. SM4 has taken it a step further by adding key switches for chord type and capo positions, I have not tried it yet but this removes the 12 chord per project limitation of SM3.
 
If you are manually strumming with SM4 I can see a potential issue where you don't have enough hands to work the keyswitches as well as the up and down strokes. I would probably set up key switches on my midi track ahead of recording the strums. Of course if you are using the strum sequencer this will not be an issue.
 
If you are not a keyboard player and not familiar with chord fingering the Indiginus method will be simpler.

After experimenting with SM4 I realize that for my needs (simple test beds/scratch pads) it was possibly a mistake to purchase OTS' Evolution and Slide but in the end I may take the time to try and make all of them useful for me.

Question for you who purchased the new Indiginus IV.  How many guitars does it have?  The original III had four: a Martin D28, Guild JF30, Taylor 410 and Silvertone Nylon.  Does the new IV version also have multiple guitars or only one?

SM4 Updated to 1.4
 
Check to make sure you receive the download emails because there have been issues in the past.
 

This has been on my "to get list" for sometime and I think it really fits my need of a quick and easy setup of an acoustic guitar.
 
Although the OTS' Evolution Acoustic is probably more in depth/detailed than the SM4, I'll put it up for sale and get this SM4.