I'm kind of a bullet freak to begin with mainly I find it interesting and have friends still making bullets and the equipment to make bullets. One of our friends owns Frontier bullets in South Africa, their Spartan line of bullets are 100 percent copper monolithic rifle bullets, along the same lines as Barnes or it could be the other way around, anyway if you measure the hollow point depth of the older Barnes TSX bullets you will find how shallow their HP depth is, unless they have changed something, whereas the Spartan bullets have a much deeper hollow point, and the driving band relief cuts are different. Both make for how the bullets opens up/expands and how far out the driving bands extends out of the case when hand loaded to a specific rifles throat/leade. No doubt the design is different. One of the reasons the TTSX bullets were designed for faster more reliable expansion IMO. That's not a bad thing it's a learning curve with any new product. In general terms with any brand of bullets what are their limits, good points and bad points. one big issue for bullet makers is how to make bullets to work in a variety of rifles /calibers and velocities/ranges, and the game animal to be used for , or target application. Do you want a bullet that expands on smaller thin skinned game such as deer or do you want a bullet that drives deep & still expands such as elk ? Where you are hunting and terrain/vegetation types will make a difference on bullet choices There are always very specific bullets for varmits and dangerous game but that's another subject. This is how anal I can get when testing bullets I probably have 30 boxes of different types or weights of 25 cal bullets on the locker other calibers I'm not quite as anal but a lot of different types and styles also. My primary concern is decent accuracy along with bullet performance that flat get's the job done under most circumstances for a specific animal type. I'm not going to say we are going to go use a 243 on my wife up coming trophy deer hunt the deer are too big, the ranges too long, for any 243 imo. There are better choices for us to choose from. I don't use my M1A which I have loaded with match bullets it wouldn't be a good choice it's great for punching paper and for war so I'm not terribly worried about game killing bullet performance per say, we have better weapons choices for what we hunt and the way we hunt. The only reason I'm going to load up monolithics for this up coming hunt is because of the Condor area we will be hunting in, if there wasn't any Condors there I wouldn't use them, I have better choices for thin skinned deer, elk on the other hand I do like the mono's but rarely use them anymore, I find at the longest ranges and the better controlled expansion bullets are good enough for my older age capabilities.