I feel blessed being able to fish the AuSable often. It truly is the "Holy Water".
If you're a fishing anon (not just fly fishing), I encourage you to make the trip. No guide needed. There is endless miles of accessible river with the most beautiful landscape where you won't see a soul. Ice cold, crystal clear water with the best native brown trout fishery on the planet. Every bend, hole and structure in that river holds fish.
The Grayling/Roscommon area is as cheap as it gets. Plenty of lodges, hotels, campgrounds and state land. No shortages of places to crash no matter your budget.
Newbies, stay out of the main branches and away from all the popular landings. They are nothing more than a fashion show of Orvis yuppies. Get the maps out and find the little tributaries, there are thousands of them with zero gear restrictions. If it looks too small and tight to fish, you're in the right spot. The fish in the pic came out of a 4ft wide creek on nothing more than a hook and worm.
Please respect it if you go. There's not too many places like that left