My contractor wants to install a different brand of solar panel from what was approved in their permit
If you're using microinverters there are some circuit calculations you're supposed to do using the panel specs and local temperatures to let you know the maximum number of those panels that can be chained together.

If you got different panels then you paid for, I hope you got refunded appropriately!  Besides initial specs, I believe mono panels age better than poly in terms of output degradation over time.