GPS lap timers

There appears to be 2 types. An "all in one" style, and the type with a seperate GPS receiver (eg Racechrono). Since all I want is to record my laptimes, and I don't need a realtime display or anything, can I just buy the receiver part and upload the data direct to my computer when I get home to view the times?

I've got the race chrono with the separate Bluetooth receiver and I can't speak highly enough of it. The feeling you get when you come in from a session and see you have just beaten your last pb is amazing.
I like the fact that it also gives you an optimal lap time to by adding all your fastest sectors together. So you know if you can manage to string it together you can go even faster 

so this is racechrono running on a nokia smartphone or the like?

Yeh you can run it on a phone which is what I did initially but then I got the custom made LCD screen for it.
I found the phone wasnt quite as reliable sometimes switching off maybe due to vibration???
Plus it came off my bike once after vibrating off and I rekon if it hadn't got stuck in my fairing I would've had a hard time explaining it to work

I use racechrono and simply put the phone inside my jacket. I have the gps sensor mounted inside the fairing. You lock the keypad to stop any mistaken key presses fouling up the timing and you don't have the distraction of watching your times during the session, just check them when you come in.