Windshield/Windscreen quality issues?

I'm the proud owner of a Portofino. I've had the car 6 weeks, and with summer weather, love the dual-personality of the car as a convertible and a coupe. However, 3 days after I got the car I picked up a stone chip which cracked the windscreen. I was gutted, but wrote it off as pure bad luck. Fortunately it's an insurance job and Autoglass in UK did a decent job replacing it with a original Ferrari branded windscreen - even though it took them 5 hours!! That was ~3 weeks ago (after waiting 10 days for the windscreen to get shipped).

On Friday, on a warm morning I decided to take the car out, and bam! Another stone chip and another cracked windscreen. And no, I wasn't driving like a bat out of hell - doing 45-50 mph on a relatively good quality A road in UK. I couldn't believe it, but it got me thinking... Is there a quality/strength problem with these windscreens or is it just horrible luck?? I have a few other cars, and never picked up a stone chip before. Granted, they're not as low as the Ferrari, but then I used to have a 911, which has roughly same height as the Portofino. Any thoughts/similar experiences much appreciated.