Acoustic samples don't do demo's. I guess as an established VI developer they have credibility and it works for them. They are not alone in not providing demo's but I agree it would be nice if they did.
GSI warn that VB3 may be incompatible on even 32 bit Macs and suggest downloading the demo and finding out for yourself. If it doesn't work - tough. If you upgrade to a current version of OSX then forget VB3, there is no interest in updating it to work with current OS's. On the other hand AS are guaranteeing their VI's work on 32/64 bit Windows and Mac and provide excellent support.
I would prefer to use software from VI developer that is committed to keeping them up to date with changes in the OS they are used on rather than be stuck in legacy land.
If that means I spend $100 on the odd occasion for something that doesn't work for me so be it. Most VI licenses can be resold so it you have the option of getting some of your $100 back if it is not for you.
MainStage 3 | Axiom 61 2nd Gen | Pianoteq | B5 | XK3c | EV ZLX 12P "Music is a journey. We are all at a different stage in that journey." James Morrison, Australian trumpet legend