So I was about to pull the trigger on a new keyboard for live use. The setup I've used for the last 3 years has been a midi keyboard triggering virtual instruments in Protools. It's been good but it was hacking a DAW for live use so a compromise ... it worked but wasn't designed for live use really.
So I saw Mainstage 3 on the ap store and thought for £28 I will try it, for that price it probably won't be great but worth trying.
Wow, I've only just got into it but the sounds are great, really usable and the performance screen is exactly what you want for live use. Plus you can configure your controllers to control any of the most useful functions.
And it doesn't need the latest Macbook. It will install on OSX versions as old as Mountain lion I installed it on my 2012 Macbook Pro, no audio interface just straight out the headphone socket and it was fine. No problems and very low latency. Likewise on my 2015 Macbook Pro. You can install it on any machine you are signed into the ap store on.
Haven't got into the guitar sim side yet but it comes with a load of amps and stuff.
£28 ... crazy !!