My dd & I read Mystery of the Silver Coins this year with RTR & loved it! We couldn't wait to read it each day (at least I couldn't!)
I noticed the first book in the series was read in PHFHG, which we didn't do (we started w/CTC). I would love for us to read the rest of the books in the series, but wanted to check with you first & find out if you plan to include them in any of the future guides. I also wanted to tell you how much we have enjoyed reading the books you have chosen for these guides. I love reading them (or listening to dd read them) as much or more than my dd!
We are now reading Morning Star of the Reformation & we both are learning so much. My 4 year old ds is doing LHTH & I can't wait to take the whole HOD journey with him. 
Thank you so much for all the work you put into these guides. It is so evident you truly have a heart for God & for teaching.
Mindy
We do schedule Book 1 in the series in Preparing Hearts, Book 2 is in CTC, and we schedule Book 3 in the DITHR Level 5/6 Boy Pack. There is also a Book 4 and Book 5 which are not scheduled in our guides at this point.