We didn't end up going to Margaret River as the 3 hour long drive was voted by all to be a bit too much in one day. Instead we took our lovely Americans to a local boutique brewery in the Swan Valley called Feral Brewing. https://www.feralbrewing.com.au/brewpub/
The guys opted for the tasting tray which consisted of six little beers each and the brewing notes for each one. Although I am not a beer drinker it was quite interesting to have a small sip of each one.
The food was really delicious and the day was once again very pleasant and not too hot making for a great day out!