How old is your Ruud air handler? If it used R22 refrigerant then you will need to change the evaporator coil. I would also recommend changing the lineset, but it could be reused providing it is flushed properly and the correct size.

Mismatched components can work together, but you have not idea what is the rated efficiency. Have you looked into getting a matching Rudd condenser?

A big mistake. Maybe you are a gambling man/woman....

IMO