As a lab owner here are my thoughts...
1. Early season chukar hunting is tough on any dog. They all need to be in good shape and have lots of water. If you watch your dog, take plenty of water for them, and dont run them into the ground, they will do just fine hunting chukar. a well trained pointer might be the best dog for hunting chukars, but a poorly trained or unfinished one has got to be the worst. I have seen a lot more of the latter.
2. i hunt in the olives and thick stuff a lot. A dog on point in the middle of a bunch of russian olives is worthless. If this is the type of terrain you are going to hunt, get a lab. The thing that will help you more than a dog in most cases, is hunting with a partner. i can't tell you how frustrating it is at time to hunt around one side of the trees only to have the birds go out the other.
I shoot lots of upland birds every year with my lab. the 06-07 season i was living down on the John day for most of Nov and Dec. We hunted chukars almost every day. (fresh chukar for dinner

) Lots of time in the field with lots of birds down. She probably wont ever be in better shape, or more in tune with how to hunt chukars than she was then.
The key to hunting chukars with a lab in wide open coutry like the J.D. breaks. is to keep them close. Do not let the dog cross a ridge or into the next draw without being be your side. When you hunt chukars a lot, you tend to know about where they will be and can work towards those areas. It also helps to really know your dog well and be able to tell their movements and patterns when they start to scent birds.