Giordana sold frames for a while. They sponsored at least one domestic pro team in the 90s. The frames were made with Excell tubing, thin wall steel. If you're looking at a frame like that then it's a Giordana. They were distributed by Gita, the folks that distribute the clothing as well as (back then, not sure about now) DeRosa, Merckx, Pinarello, a couple others, plus Duegi shoes and other smaller brand stuff.

They have different models. I'm only familiar with the lightest one, it was in the 3-4 lbs range for the frame, they had very clean looking seat clusters, no significant oversizing on the tubing. They're pretty light for a steel frame but the tubing is very thin - I think the top tube was 0.8/0.5/0.8 mm thick, similar to Tange Prestige of the same era (Excell might have been quad-butted, I don't know, so potentially 3-4 thicknesses). It's nice, responsive, but if you put a lot of miles on the frame they'll crack sooner than later.

A friend of mine raced for one such pro team and he went through a few frames a year. Given that he was doing somewhere in the 15-20k mile range each year the frames probably lasted 5-7k miles under a pretty powerful rider. The cracks were in the seat cluster area on the seat stays and the BB area on the chainstays.

The heavier frames ought to be much more durable - more metal means more resistance to fatigue, to overheating when brazing, etc.

Hope this helps.