We find the Charollais relatively easy lambing - very fine, light fleece helps keep the lambs slippery, and they seem to be born rather slight and get solid as they grow. I like 'em! They always seem to have loads of get-up-and-go, and like their food and know where to find it, too.
The only thing we have to watch is if they are born into cold wet or windy weather and the ewe hasn't got them well sheltered and doesn't lick them vigourously and quickly, and maybe doesn't let them feed straight away if she's a first-timer, then they can founder through getting chilled, being so thin-skinned. So we bring in anyone looking likely to lamb if the weather is expected to be unkind.
Our ewes are commercial Texel-type and North Country Mules, not Hebs, mind. I don't know how the pelvic opening compares between ours and Hebs. Swaley Mules are pretty roomy, Texels less so, especially gimmers.
Good luck!