I'm due to be starting my first real job out of education in 3 weeks time, but I've been having some second thoughts about it. The job pays less than the equivalent role in almost every other firm, but I had taken it because it seemed to offer two compensating benefits: shorter hours and more interesting work. At the time of applying I wasn't sure exactly what role I would receive, but these are characteristics of the firm in general (shorter hours and more interesting work).
However, a couple of months ago I was given more detail about my role and these benefits now seem to be negated. It seems that my hours will be just as long as those in other firms, and from what I was told, it seems that the work will be less interesting and there will be less ability to develop skills that are essential to progress in my line of work. These seem to be disadvantages of my role specifically, not the organisation as a whole, so I just seem to have drawn a short straw.
The lack of interesting work and skills development worries me a lot more than the hours. For instance I worry that if I want to move elsewhere after my three year contract finishes, I would not have the same level of required skills as others would after three years.
However, I'm not sure of any of this. These are just my own inferences given what I've been told and what I've managed to find out from others, and none of that has been concrete. I would say that there is a 40-50% chance that the work will actually be interesting and challenging.
As such, I'm wondering what the best way to proceed is? I have a one month notice period once I start - would it be unprofessional to work for 2-3 months and if my suspicions are confirmed (and I can't negotiate any improvements) to then quit? (One point to note here is that it is essential for them that they have someone in my role at all times and so the transition period would probably be a pain for them). I'm aware that it's probably better for them if I quit now (and I wouldn't have to explain the short period of employment or lose as much reputation in the industry), but there is a significant chance that the role would actually be a good fit for me, and I can't really know unless I try.
Thanks in advance for any advice!
(edit: I forgot to mention a couple of points:
Spending an extended period of time (3-12 months) without a job isn't a problem for me financially, and the few companies I've spoken with before have said they wouldn't mind the gap in the CV after education.
My industry is fairly incestuous, and getting a new job is my main worry when it comes to quitting. When browsing through firms that offer equivalent roles, I've seen quite a few people who have worked at the firm I'm supposed to be starting at. I don't know if reputation ruining happens often with people who quit early? And would 'I wasn't learning/being challenged enough' be a valid explanation if asked by any new employed why I quit early? Whereas if I quit before starting, I would presumably avoid a lot of this.)