In reply to williap:
Apologies for the delayed reply on this, I'd completely missed C Rettiw's original question.
There's definitely similarities between them, insofar as they're both stiff/supportive shoes designed for performance trad/sport; however, there's also some quite significant differences.
The Miura VS actually feels quite old school in terms of its construction. The support comes from the the fact it's got a thick, solid midsole. The Boostic R, in comparison, features all the tech construction-wise and the support comes from that in the form of the shoe's randing, tension and also the midsole, but the other factors play a huge part.
The strength of the Boostic R is also that it's a lot more adaptable, whereas the Miura VS feels a lot more one dimensional. If you stand on a micro edge the Miura VS is incredible, but if it does get at all smeary then the Boostic R would be the shoe you want on, because it's capable of a much wider range of use.
This isn't to say that I don't like the Miura VS, because I do - they're absolutely great; however, they're just a little more limiting.
As always though, try before you buy!!