Mine takes 2 seconds. Never seen it take 5 seconds. Not sure why yours differs to mine, as mine has always had around a 2 second delay with all the different roms/firmwares etc i've installed.
I have mine being saved to external card. The delay doesnt seem to change if I have it set to phone or card, but I dont have a great deal on either. Have you tried changing this setting?
I've not read anything that can be done about this. I would be interested to see if there is, as a 2 second delay for me is annoying enough.