Flemish giant crosses can make good meat rabbits.
It all depends on what you are looking for though.
I find that they are often more docile than new zealands can be. Not always, and not all new zealands are feisty. Many people tell me that flemish crosses have larger bones, but I haven't weighed new zealand, cali, and Flemish giant mix bones to compare them.
An adult doe with a 3 week old litter is probably the worst possible choice for a beginner to start on. The kits are very delicate at that age. Moving them or changing their diets could stress them greatly. Stressing kits can increase disease susceptibility, lower growth rates, and possibly be fatal if a GI imbalance occurs.
The price is a bit high for meat mutts in my area.
Pedigreed calis and New Zealands are sold around the same price as that buck.
Kits aren't really worth much until they are weaned, because weaning enteritis can cause losses. For that reason, meat breeders judge the value of a doe by how many kits she successfully weans, instead of how many she gives birth to.
Is there something special about these particular rabbits to warrant the higher price tag? (organic, non-GMO fed?)
Why are they selling the doe with a 3 week old litter? Are they getting out of rabbits entirely, and if so, why?
Are they skittish and hard to handle?
Are they sick? (sneezing, diahrea, bloated bellies?)
Do the kits growout too slowly to make them economical?
Is the doe mean? ("Protective" is often used as a coverup term for "animal that bites".) Mean does do NOT make better mothers than calm does.