[drdisque]

I generally feel that offsets within 8 mm are fine. Think about how small that difference is its less than 1 cm. As long as fitment isn't an issue, I wouldn't hesitate going with a wheel with a +45 mm offset or so, +42 gets a little hazy. Overall, the lower offset might actually improve handling but make the car's steering feel a little slower. I wouldn't worry about excess stress too much, again 8mm isn't much from a weight/stress standpoint.

Most quality modern wheels seem sufficiently strong for road driving, regardless of weight.