In the last post, some guy left a question in the comments about the fact that he is straight out of the lab and has an offer to be a product manager. Wants to know what to expect. AND also has an idea for a start up and wants to know about that.
So - to deal with the start up first. If it is in the Bio area, and you have no business experience, I wish you the best of luck. It is possible that your idea is THAT good. I don't know. I would doubt it and would guess you have a long road ahead of you making errors.
THAT SAID - if you believe in it and can't live without doing it and don't mind working your butt off and probably not making any money - worst case -> you will come out of that with a lot of great experience. Best Case -> you get rich. Only you can make this call.
Entry to the business world. There are at least two jobs that dress themselves up as product managers. One is a tactical role and the other is strategic.
In a tactical role, you will be doing things like putting flyers together, scouting the competitions pricing and running promotions to combat them etc... You will have minimal involvement in product development and will really only be focussed on the next 3 months. You will give feedback to the strategic folks and hope that your ideas lead to a product. There will, likely, be a bit of friction there for everyone to overcome.
In a strategic role, you will not be too involved in the day to day stuff. You may get sucked in to some sales training (depends on the company) but will likely be mostly focussed on what products do we make next. How much can we charge for them? How much will they cost to make, and can we make any money at that price? Those last questions translate to "should we make them".
At many of the companies, and I have an idea about who you could be going to, the roles are blended. There are not seperate folks for the strategic and the tactical. I think this is the best place to learn as you can see what you like and don't like. A general idea would be that the bigger the company, the more "silo'd" people are. Break through 1000 people, and there is likely a split between tactical and Strategic. Below 500 - there probably isn't. In between - All bets off.
He also asked if his shot at getting offers from other places is good. Hard to say without seeing your resume, but I would likely go with the first offer I got just to get in the game (what I actually did when I got in to it). Getting a second job will be MUCH easier with the first one out of the way. If you want out of the lab, I would get out of the lab.
You guess at 80-90K for the pay. I wouldn't rule that out, but as someone just coming out of school you might drop in to the 70's. Depends on the company and what the bonus looks like (i.e. lower salary may have higher bonus - not guaranteed but I would expect it).
I like places with growth, and would be attracted to that. No matter what - you will learn a lot. I would get on with that learning and not wait around.