The 1/2 he played vs KC, and the following start, you could tell his timing with WRs was off, his reads were a bit slow and that he wasn't doing a pro QB workout during his time off. The positives you could see, were that his arm/elbow had recovered to at least 90% of what it was and that he wasn't overly sensitive about guys on the ground around his feet/knees. Those were his two biggest questions regarding his ability to be a high-end NFL QB for the remainder of his career, and I think he's answered them in an impressive manner. He will continue to improve timing with practice, and will get more and more comfortable with his reads as the playbook becomes 2nd nature rather than an effort to remember between breaking the huddle and taking the snap.
He makes better throws than any QB I've seen in Oakland with the exception of Gannon (too young to have seen pre-90's QBs). Oakland scored big with this one, and what was generally viewed as a butt-raping by Cincy initially, could very well be a win-win deal. I think he is still a very good NFL QB, and should be a borderline #1 FFB QB. I still think Oakland will put an emphasis on it's running game, and big passing numbers will likely come from necessity rather than habit, so I doubt he ever sniffs top 3 for a season which is where value lies in fantasy. If you landed him as a backup or replacement, you should be sitting pretty whether redraft or dynasty.