Mine still working as of June 9th
I used my Google prepaid card at McDonald's yesterday (Sat 6-9) for breakfast with no issues. Mine has been set up and working since May 24th though.
I rooted last night using the perm root only method (to get Titanium first) and could not get it to initialize(after clearing Wallet after backing up). Restoring the app data fixed it. Did a full root with recovery after clearing Wallet today, same problem, Titanium fixed it again. Have not tried to pay with it yet since, will report back when I do.
Seems if you have a phone with working Wallet, you can preserve it with Titanium.