Keep in mind that I selected the Sendero SF (Stainless Fluted), not the regular black matte. The difference in weight is about 1/2 a pound lighter and not as front heavy. I bought this gun at a time when the .300 Ultra Mags were (and to some extent still are) popular. I thought to myself - 1000 yard benchrest shooters shoot 300 Win Mags, not Ultra Mags. So accuracy should generally be good from this cartridge. As such, I went ahead and got the 300 Win. Mag. As for the Sendero SF, I had heard many good things about them. The HS Precision stocks with full length aluminum bedding block sounded stable, and thicker barrels reduce vibration, and thus can enhance accuracy. Another reason I got the SF was because I got a great deal on it. $700 including shipping - NIB - sealed box!
Now, if I had a choice between the Police and the regular Sendero - like I said - pick both up and see which one feels better in your hands. I think that the Police is about $100 or so more than the Sendero. I also think that the Police stock from HS is more expensive than their Sendero stock - as such, this may be part of the reason why the Police version is more expensive than the Sendero version.
The Police version are harder to locate, and, as supply and demand go, you will not be able to get as good of a deal on a Police than you normally could with the Sendero. Either way, you can't go wrong with either gun. Just see who gives you the better deal.
Zachary