'seeing the heavyweights in videos doesn't come close to seeing them up close & personal!' So true. And there are a lot of good robots, in all 3 classes [60 lb, 120, 220] and about half of them are spinners.
'After looking at the RG 2013 lightweights, I don't think there are many feathers that will stand up to the US and Brazilian bots - I just started my first lightweight with 10mm armour; its going to be needed!' In 2012 I built Oakheart, a 6 wheeled pusher that was built entirely out of wood. I wound up fighting a very good Brazilian drum spinner and when we hit, head on, there was a shower of chips and splinters but Oakheart kept going. The Brazilians won but afterwards they all came to my bench. Every time they had hit another robot head on in the past, the upward spinning drum had launched it into the air and they were puzzled as to why it had not happened this time. I had screwed an extra piece of 2x4 onto my front bulkhead and it had absorbed most of the energy while being shredded. The 2x4 was chewed up but the underlying bulkhead was untouched. Took a redesigned version of Oakheart to the 2013 games and had fun but didn't win.