How's it hangin Jesus!! [/always wanted to say that!!]
For a lappie, all I would suggest is have the standard client running away in the background when you are on doing lightweght stuff like surfing, documents etc.
For any other rig, I would say 'always on is ok' but for something packed tight like a laptop, I know from personal experience what prolonged use/overheating do. I have a tablet pc, I treat it with the same caution!
Upload/download size isnt large if you are running standard client and havent configured the client to go far larger/advanced projects.
Asinus asinum fricat