I'm very impressed with my Andreani equipped forks on my Strada. I rode a new, stock 'Strada ... NO COMPARISON to my bike.
I'm not sure what fork springs are in my bike, might be heavier than stock.
I would look to see what Andreani recommend. Sometimes with fork cartridge systems you do not need heavier springs, sometimes you do.
i'm about 200 lbs. and I have never bottomed out ... even OFF ROAD! So could be previous owner of my bike upgraded springs??
Overall the front end is one of the best I've ridden (over 40 bikes!) My rear shock was reworked as well so overall, a magic carpet ride on my bike. Very nice indeed. It's the whole reason I bought the bike. We have lots of beat up, bumpy roads around here. (NorCal) the Strada eats them up!
springs are included with Andreani cartridge system. If you order one you tell them your weight and get the appropriate springs.