Found this with a simple GOOGLE search:
I just want to give some more information on PRL Updates for those people that just LOVE to rush out and get them. Hopefully, this will dispel myths:
PRL Myth vs.
1. Updated PRL will fix manual roaming issues.
No. Manual roaming occurs when the customer is asked to enter a credit card to complete their call.
This is caused by the Roaming Network needing a table correction because it doesn't recognize the Sprint MSID. A trouble ticket must be created to resolve this.
2. The PRL needs to be updated so my phone can acquire the signal from new cell sites.
No. The PRL does not use individual cell sites as the driver for connecting with the network. New cell sites are normally integrated into each companies own network. Once the cell sites are active they function just like all other cell sites because they broadcast the same SID.
3. The PRL is only used to acquire roaming partner signals.
No. The PRL is used to acquire both the Sprint network and our roaming partner's network.
4. The PRL will fix a majority of roaming trouble issues for the Sprint PCS customers.
No. Many roaming troubles that affect customers are network related. It is very important to create a trouble ticket for any roaming related issue even if the customer has an outdated PRL.
A PRL will not help with:
Improve signal strength in Sprint or roaming areas
Quality issues (Echo, Static, Cross Talk, Audio Weak, etc.)
Coverage holes (No Service is available to make or receive calls)
Fast busy signals
Providing added features to a Sprint PCS phone (such as voicemail)
Wireless Web issues
Receiving a Sprint PCS error messages on outbound calls
Correcting misrouted calls when roaming
Receiving a credit card prompt while roaming
I hope this answers some questions for you guys.