Like my 500, but the road noise is maddening. How is the road noise in the 500l?

Tyre choice can make a big difference to road noise.
EU introduced tyre labeling which includes how noisy they are.
Maybe worth having a look to see if you can find some quieter tyres.

It's not too bad in our trekking!

Much quiter below 60mph, motorway speeds are ok though. Going to fit an under engine tray soon, hopefully that'll help too! As most new fiat's don't get them now..

Compared to our panda 100hp, which I'd consider may be similar to the 500 - it's definitely alot quieter!

Well, I tried one out and bang! No road noise! Bought a Trekking. What a nice vehicle!

Congrats ?

Best model

The standard 500L should be even less noisier, since (at least here in Austria) the trekking has M&S tires and not 'ordinary' summer tires.

yup very quiet.