My tank came in. Initial fill pressure??

Got this scba tank off of Ebay after watching ztirfrittz's build. It looked fairly grungy, but most of it was adhesive that came off with Goof Off adhesive remover. The tank cleaned up well and was $135 with shipping. I purchased a pre-made scba connector and whip for $165 shipped, because it looked like I would spend that much to build one. That's $300 for the whole set-up. 4500 psi 45min. tank. The tank is 2008 manufacture date and it will be less just to buy another one in 7 years than to spend $800plus on a new one. My local fire department is going to fill it for free. Thanks for the guidance ztirfrittz.



 
The firehouse filled my tank to 4500psi and they did it slowly to keep the heat down. It still took less than 15 min to get it done. The tank was quite warm, but not so much that it couldn't be held. I did notice that after cooling the psi held at around 4300psi. I am assuming that's normal with cooling. This was my first fill. Do most of you experience this and do you have it overfilled slightly to make up the difference, say maybe 4700 initially??