My short answer is: I'm Waiting to See how the sync of a RootsMagic database with an Ancestry Member Tree works once it is released.
1) What I don't know:
* Will the whole RootsMagic file be able to sync with an Ancestry Member Tree, or will the sync be for one specific person at a time, or will it sync one event/note/source/media for a specific person at a time? The first option is what Ancestry.com synced with Family Tree Maker 2008 to 2014, but Ancestry has said that won't be the case sometime after 1 January 2017. The third option is how RootsMagic (and other programs) syncs with FamilySearch Family Tree at present.
* How will the transfer of Hints from Ancestry to RootsMagic will work? Will it capture the record image and put it in my computer files, and add Event(s) and the Source to a specific person in my database? What about a record for a group of family members, like a census record? What about a multi-page record for an event, like a 20 page probate record?
I dislike Ancestry.com's source citations and don't want them to make extra work for me to fix them - I'd rather do them myself in Evidence Explained format and not crap up my source citations with Ancestry's poor citations. I try to standardize all of my place names and really don't want to crap up my place list with Ancestry's inconsistent and non-standard place names. I have document images and photographs in specific family files with a file naming convention for my ancestral families, and I don't want to have to find an image captured from Ancestry into RootsMagic and determine where RootsMagic put it, then change the file name and then move it to my family files. I think I will continue to download the record image when I find it, download it to my computer, rename the file using my file naming system, and put it into my family file system.
I really expect to see an Ancestry green leaf icon on the name lines to enable the sync feature with an Ancestry Member Tree for matched persons (similar to the FamilySearch blue icon for matched persons).
2) My plan is:
* Get my RootsMagic database as up to date as possible. I continue to add persons, relationships, dates, places, notes and sources almost every day from Hints and Record Matches on Ancestry, FamilySearch, MyHeritage, Findmypast, GenealogyBank, and AmericanAncestors, plus information from other online or repository resources.
* I don't want to use a current Ancestry Member Tree because the one I am using for Hints is 2.5 years old now, and doesn't include 4,700 persons, and tens of thousands of events and sources, which I've added over the last 2.5 years.
* When the RootsMagic sync feature is stable, I will create a new GEDCOM file from the RootsMagic file, and upload it to Ancestry.com and will then sync the RootsMagic file to that tree.
* I will then sync persons and/or events, notes, sources, etc. (depending on how the sync works!) when I add content to RootsMagic. Most of my syncing will be from RootsMagic to the Ancestry tree, and not the other way. Ancestry immediately should create Hints for a new person added to the Member Tree, or even when new data is added for an existing person. I will need to use those Hints to capture the "low hanging fruit" records for a new or existing person. This way, I will keep my RootsMagic database current.
3) That's my plan. What's your plan?