Is't the only game in town. I bought my HP when they were phasing out the 2.8 and they sent me 2.4 I realized rather quickly that something was wrong, the screen did not act exactly the way tyrg explained in his review. It did not work very well in ambient light. The surface was not smooth like he said, and it was rather thin feeling.. After a looks at the surface with a microscope it was very obvious that the screen I had been sent was not the same as my 2.8 sample. At this point the website still said 2.8 but they were shipping 2.4 and as 2.8
There is a thread on this subject with pictures.
In the end, they sent me the 2.8 and I had both side by side, the 2.4 went back. Of late there have been several complaints about 2.4 screens being blotchy or having dark lines. There were also complaint about the 2.8 on occasion.
Other than the lower gain the 2.4 has less of a drop off of gain at then end and a little less red sift off axis (less micro beads and more white emulsifier).
It is an inexpensive screen that works really well if all caveats are met proper. So as a 2.8 owner, you should be good to go.
If there is nothing wrong with you 2.8 why are you thinking of replacing it?
If yo have not washed you 2.8 you may want to do that, it will be some work but with a fantastic payoff you won't get with a new 2.4 screen.. it will be like new again!