I can empathise with your situation although my own situation is somewhat different. OCD has affected my work, whether it be as a student or employee. I am a complete perfectionist and have the highest standards with regards to everything that I do. In some ways, this has been a good thing. I would never have achieved half of what I've achieved were it not for my OCD. In other ways, however, it has stressed me out terribly.
If you've seen my other posts, you'll see that I graduated with a masters degree in Dec., 2008. Due to the economic climate, however, I've been unable to get a suitable job and have been working part time in a job that I was doing before I even left school. I've been off sick for about three months now. My anxiety levels have gone through the roof. This is partly because I've been trying so hard to get a better job to no avail but it's also because I just do not belong in that type of workplace. I don't mean to sound bigheaded, but I know that I'm so much better than that job. I look at my peers and superiors there, and all that I can see are faults and incompetence. Their standards fall far short of my own.
I would do anything to be in a more challenging job where my anxiety was being caused by my wish to succeed and produce work of the highest possible standard than being in this thankless position where my anxiety is being caused by feelings of isolation and a complete lack of achievement.
This job that you've been offered presents you with a challenge, not only because it sounds like a decent position of work but also because it will force you to face your OCD head on. The OCD may well help you to do your job well and you must acknowledge that fact but you must also create a balance whereby your standards do not become detrimental to your health. It can be difficult but it's possible and, when that balance occurs, can produce the most amazing sense of achievement.
I'm not sure if this makes much sense (back to my perfectionism) but it's always so difficult to express such deep feelings. I just thought that it might be useful for you to see the other side of the coin. I do hope it helps and wish you well in whatever you decide.