Considering applying for a third PhD Program after having bad experiences in two
I guess I don't understand your dilemma. You have an offer. If it seems better than your current situation overall, you should consider taking it. Your age is not material to such questions. You will eventually be 50 and then 70, if you are lucky, no matter what your choice is now. 

If you've been misused in the past, don't let it color your decisions. 

But, make a list of the positives and negatives of each possibility and then choose what seems to be best.