i have an old bianchi piaggio, is it a good deal if i trade it for a bianchi strada lx?
they are both from the 80's
which bike is better?

Piaggio was (still is) a large Italian conglomerate that bought Bianchi in the very early 80's. They very well may have been the owners of Bianchi when the strada LX was purchased. You need to say what the parts mix for the piaggio bike is, before anyone can tell you what kind of bike you have. In general you'll have better luck posting this kind of question on the Classic and Vintage thread.

the piaggio was made in japan with mostly shimano gear i dont know much about the strada lx, mainly interested in comparison of the frames