Low on springs = good but damn inconvenient as i've seen my friend's friend's Integra scrape on a speed hump
Low on bags = expensive and usually take up the boot, but is a bit more convenient.

So personally I'd prefer a car that is practical (hard shocks, not cut springs or bag's as they go around $1-2K) then just all for show, no point having a show car when you have to be careful at every speed hump or any mod make the car totally impractical.

Also to clear thing up A bit of camber = good as it give 'stance' to the car ( lol I'm starting to hate that word... stance <_< )
But too much camber just looks stupid: http://www.youtube.com/watch?v=_r6ltUgtFW

cars l.ook better low , but i think you should still be able to put your hand underneath the car lol

Well, ridiculously lowered cars look... ridiculous. Never combine a lowering with humongous rims, Clay Aiken will cry tears of blood then.

Some flush CD5, CD6, and CD7 accords from Eibach

hahah, every car ive ever owned couldnt make it over a speed hump straight on, have to crawl over sideways =] You learn to get used to it. But i lower my cars for a completely different reason than looks but i guess im just lucky it looks nice in the end =]

And as you said, Bags are too much. Not just in price, but they make general driving feel quite shitty (compared to a decent spring/shock combo). If you want your car to hop, just get more torque Friends have been able to dump the clutch then hard brake, dump the clutch then hard brake ect and weve actually gotten the front wheels off the ground like 20-30 cms hhaha

As for how low is truely impractical?
anything lower than DTM spec cars, and it is 100% pointless lol.