When it comes to either collar, the main concern is proper usage.
--Chain "Choke" collars are just that; the reaction of using a chain collar is essentially a --quick-- choke used during a verbal command.
*Size matters. When selecting a gauge size for a choke, always pick a suitable width. For a larger dog (40lbs+), gauges of 3mm+ should be used. By using too small of a gauge, you --can-- erect a possibility of severing into the dog's trachea when utilizing the choke. Also, you'll want at the most, 2" of slack in the length of the chain. Anything less or more defeats the effectiveness of a chain collar.
*Placement. For proper control usage, the collar should rest directly below the base of a dog's jawline, at the start of his neck when being "used"; It should never rest lower.
*Chain collars can cause severe trauma to a dog's trachea, especially when not used properly.
Choke chains should **only** be kept around his neck when you are doing training with your dog; It should ***never** remain on unsupervised. Chances of one of the loops getting caught on anything is great; causing the increased likelihood of your dog choking to death.
-Pinch collars are designed exactly to "pinch" the skin around a dog's neck as a training technique. (Be aware that the pinch for some dogs, can be painful. But, in general its reaction is of a slight sharp pinch, like one we'd give one another with our fingertips.)These collars are especially useful for larger, stronger dogs that chokes, harnesses and nylon collars cannot control. The prongs on a pinch collar are dull, flat edged and face at an angle to prevent any possibility of puncturing into the neck. Basically, when pulled taut, the prongs angle to pinch the skin around a dog's neck.
*Size matters. Just as chain collars, pinch collars should have 2" of slack.
*Placement is also just as the chain collar; sitting below the jawline, at the top of the neck.
***Pinch collars should never be left on the dog when not in training use, too.
Between both collars, I would be more apt to use the pinch collar. It causes the **least** amount of trauma and produces a more effective action; thus rendering a faster, better response from your dog. Especially when dealing with a "headstrong" dog, a pinch collar will give you the results that choke's just can't. IMO, it is a **much** safer product then the chain choke.
Many "judge a book by the cover" because of the prongs, but don't let it fool you. When I first was introduced to them, I myself was very put off by them; I considered the prongs so inhumane. As time went on, I learned what they provided and how much better they provided it; especially opposed to chain choke collars.
Its imperative with whatever choice you take, that you remember the importance of verbal commands when using these products. Choke and Pinch collars are secondary to verbal commands.
If neither option fits your choice, consider the Nylon Choke collars (as one person's mentioned) or a head harness. Nylon Choke Collars work on the same premise but use are considered more humane then the chains. Head Harnesses like "Halti's" or "Gentle Leaders" work fabulously, too. They work on the same basic premise as reigns of a horse. You control a dog's (usually a walking trainer) behavior by pulling his head against the direction he was already going. While I like to recommend them, I don't with dogs that are highly dominant or those that are training for other purposes beyond walking.
**Edited after reading your addition**
You shouldn't be needing to yank so hard to get him to follow your commands. (The more you have to pull or the harder you have to, just will cause more harm to him.) But, obviously this is the reason why you are asking the question between the two collars. While this time of his "childhood" is the most impressionable, best time for training, if he's having the opportunity to make you work harder for him to obey your commands, it may become the best time to change the method.
Consider for a short period of trying out the pinch collar. Use the pinch collar in an easy situation, like walking, without any type of distraction (for instance, in your living room). This quick opportunity with the pinch collar should garner you if his reaction to it as the same or better then with the chain.
Besides that, how long have you been with this trainer? If you've been seeing him/her for longer then 3-4 weeks, it may be time to consider another venue. Perhaps there are different techniques by another that can be more beneficial for you and your pup.
In anycase, good luck