Rather than spend a lot of money on stuff that likely will not result in much of actual improvement on how you shoot order an Apex striker block and a lighter trigger return spring and you will find you have a very nice smooth and lighter trigger pull. The reset will not be quite as fast as you get from either of the kits I mentioned and you still will have the hinged trigger but you will notice an improvement and save yourself a significant amount of money. Unless you are a very accomplished shooter you likely will get little benefit of a faster reset anyway, Oh you notice it when you are in the rumpus room in front of the TV set but when shooting quickly in IDPA or IPSC you will never notice how fast or slow the reset is. The reset though will be fast enough. Master type shooters would be able to take advantage of the faster reset but for most not so much.
I have the Competition Kit in my M&P Pro, the Pros innards in my old FS both in 9MM. I have the FSS Apex deal in my 40 Pro. The FSS trigger group does reset the fastest but you would never notice it in my scores. The flat trigger is different to be sure but not better IMHO. I do have a FS 40 with just a reduced trigger return spring in it and the trigger pull is lighter which makes the longer shots a bit easier.
I should add the Apex striker block is domed much more than the factory block which takes away the gritty feeling you get when pulling the trigger on an unmodified factory pistol.
Take Care
Bob