To answer the original question, which was (paraphrased) "Can you suggest a good small scanner for scanning police activity in the Hilton Head/I-95 area of SC?"
I'd suggest a PRO-164 (Radio Shack), PSR-300 (GRE) or BC246T (Uniden).
The South Carolina Highway Patrol performs traffic enforcement on I-95 in SC. Their radio communications are carried on the Palmetto 800 trunked radio system. Their talkgroups are not digital, so an analog trunk tracker works fine.
Hilton Head LEs operate on the Beaufort County trunked radio system. HHI itself is patrolled by the Beaufort County Sheriff's Department. At present, their talkgropus are analog as well, though that is likely to change in the next 12-18 months. Beaufort County has recently approved funds for upgrading their radio system, and it will likely include digital talkgroups for LEs.
As noted above, a scanner isn't very good at preventing someone from being pulled over for speeding. But it can help you know where concentrated speed enforcement is occurring, if you know what to listen for. And besides that, it's interesting.