This is a complex question
A good bar uses harder steel or even hard metals, which wear better, hold their shape better, some are lighter than a standard bar, sometime they are diffrent shapes for a special application, in the end it depends on what you need.
The tip which is better depends on what you are using it for a sprocket tip tend to have less friction and allows faster chain speeds, the replaceable tip is nice since the tip tend to wear out faster then the rest of the bar so you can replace the tip for a faction of what a new bar costs. however there are cases and uses where a solid tip is preffered or a replaceable tip is not the best so it all depends on the planned use
The next question you need to ask is all this replaceble tips, better metal worth the price which again depends on use or the amount of use.