Even if the quality were "only" as good as Roden's, I'd spring for one of each, just for the novelty.
Though the S.XIII might be more attractive to a wider audience, the S.VII and SE had many users, both during and postwar to make for many interesting schemes. I like cobbling together markings before the AM guys produce decal sheets, and 1/24 scale would make it easier to do serial numbers, weight tables, etc, from commercial "rub-on" transfers.
As for Des contacting Merit directly: Great Move methinks. One would think that his website would me a MAJOR channel to the market, especially those who would wait for a review before purchase.
Saving pennies and ready to put more on ebay,
Rob