Hello alljazz and welcome to the forum.
(I edited the thread title to make it more focussed.)
The best things to do is download, install and authorize "AmpliTube Custom Shop". As well as installing AmpliTube 4 ("AT4") it will install the Authorization Manager and Custom Shop standalone programs.
Use the Authorization Manager to activate AT4. You will have a few gear models available.
Run the Custom Shop and you can select to Try out any of the other the gear models for yourself. The trial period for each gear model is 72 hours, then that gear model cannot be tried again for 6 weeks. But 72 hours with each model separately should give you plenty of time.
Details are in the User Manuals that are also installed.
And AT4 MAX is at a special price until 03 August 2020:
https://www.ikmultimedia.com/news/?item_id=9690