02 CR250R pipe question

I am in the process of fixing up an 02 CR250. I am getting ready to buy the pipe and plan to go with a PC pipe and either the 304 shorty or factory sound. Application is MX. Currently the engine will be stock although I may have PC port it and modify the head down the road. I plan to run C12 or an equivilant. Carb is a Keihin 38mm airstriker.

Back when I had my original 02 (before I jumped on the 4-stroke wagon) I had the pipe and full length factory sound. My question is this. Is there any advantage in going with an 03-04 pipe over the 02 specific one? I wasn't sure if those pipes were better or just changed to match updated porting. I know the 05-07 (I think) went to the different flange setup.

Also, is there anything to gain by going with the shorty other than more noise and likely more frequent re-packs? For reference I am a 40 yo just getting back into riding after 4 years off. I was a decent junior/backmarker intermediate when I stopped.

Thanks!