I'm glad to report that the Salsa Anything cages I've being waiting for have arrived this morning. It's been quite a struggle to get them but thanks to Adrian in the US they're now fitted to the orange Inbred. The Salsa minimalist rack arrived last week but that was in stock at the UK distributors so didn't require any underhand tactics to buy!
The rack has a weight limit of 5kg which doesn't sound like much until you consider that my entire kit only weighs around 6kg. The cages don't have a stipulated limit but I'm thinking you wouldn't be putting anything heavy in them ... just bulky. I did have a few concerns about clearance between whatever was in the cages and the frames downtube but these seem unfounded as long as you don't go too mad with the height of the dry bag you fit ... the pic shows a 5l dry bag in there. The rack and cages come with some rather nice Salsa straps which while not a deal breaker is a nice touch.
Even with a loaded rack there's still room to run a bar harness if required without the 2 things getting in each others way. I'm hoping that teaming the rack and cages up with a frame bag and bar harness will open up a few different carrying options particularly for winter trips or longer multi- day excursions ... I'll let you know if I'm right.