Depends on how big you are, what you want to use the wheels for and what other wheels you currently have. Let me know that and I'll let you know my opinion.
I was thinking more on the line of which retailers are discounting...
But, since you asked, on my last & current bike I've always had hand builts. Last time they were 30mm Kinlin w/CX Rays and WI hubs, 24 spoke rear. I went through three rear wheels (mostly cracks on eyelets); I shit you not. All built from reputable builders (on this forum). I weigh in a 160; spin small gears, anyway, I 'think' I am easy on wheels. I built up a new bike in September, had 27mm Kinlin's, Lasers and BHS hubs, 24h rear. Again, built up by reputable builder. Just cracked the rear along the side of the eyelet. I have bad luck w/hand built's and am going for some Dura Ace wheels. I ride hilly terrain, not always sustained climbs, but good mix of climbs, rollers and flats. We have great descents here too. I just want a one trick pony. C24 or C35 decision will also depend on price (if there is a change after tomorrow). I can see C24's today at ~$730 to my door. Which, IMO, is a great deal.