I'd think thalls… i have my first year step ups and they are pushing their 2nd and a half season now.. no edge cracks no de lam, nothing but some base shots that aren't even that bad… BUT they're really stiff and pretty heavy.. they weigh as much and my bent chetlers to give you a little perspective. so they're bomb proof.. but heavy and stiff… the thalls, from what i understand, are a lot more flexy… and they look dope.. I've heard nothing but positive remarks on them. so if you want a stiff ski for huge jumps and would survive a nuke.. go for lines, but if you want a flexier ski thats by a guy who knows a lot more about skiing than all of us combined… go thalls.
Step ups are stiff afterbangs (from my understanding) and thalls are softer ar7's. I've ridden ar7's and loved them and I have a friend with afterbangs who hates them because of the weight. I would choose the THalls because they seem to be a more jib oriented ski where as stepups are jump. I ski wentworth too and we don't really have that much for jumps the majority of the time.