I have some people telling that the jp springs are just as good as buying a high end trigger group.
To the OP's question: I know it sounds insulting that a $10 spring kit is "as good as" high end trigger - but for most shooters it is true. $200 will get a you a lot of range time and ammo.
Anybody can tell the difference between heavy and light trigger - and the springs will give you a lighter trigger. AR-15 starts with a really really good trigger by design, and it takes a lot of trigger time to tell the minute (important none the less) differences you get with high end triggers.