I would put a roll of film through it to get a feel for its quirks and issues, if any. At least you'll know what to expect should be adjusted when you get it back from a CLA.
Regarding the lens. The first A' were delivered with Tessars made before the war. These were uncoated, so Zeiss coated them before delivery to F&H. Its been claimed that in the process a lot of the matched lens sets got mixed up, giving the A an initially very bad reputation. F&H recalled all cameras and retrofitted them with Opton Tessars. Some may of course have been OK to begin with and never sent back. The latter batches all had Optons. In any case the proof of the pudding is in the shooting. As Mike says, the 2.8 Tessars were in any case not that well reputed, but should still perform well. If I was to run into one for a steal, I'd buy one out of pure inquisitiveness. Good CLA resources in the USA are many, Harry Fleenor, Krikor (Krimar Photo), Mark Hama to name a few. But there are others.