How low is too low

For starters I dont own a bike yet. Im looking at the gsxr 600 to maybe start off with. I'm 5'5" and was figuring I would have to lower the bike some. How much is too much when lowering it is the first question. Also how much height can I save switching the seats to one of the gel-pad seats? Finally, what affect does lowering a bike have on safety, handling and control, braking, cornering, rough roads, comfort and whatever else I may have missed  

WELL AT YOUR HEIGHT, YOU MAY NOT HAVE TO LOWER IT... MY GIRL HAS A R-1.. AND HAD TO DROP IT 3 INCHES TO TOUCH FLAT FOOTED... SHE IS 5' 1" IN HEIGHT, AND FROM THE DROP-HER BIKE RIDES WITH VIBRATION AND IT CAN BE COMBERSOME ON LONG RIDES IN THE HANDS AND ARMS...NOW THE SEATS IT MAY BE A MATTER OF 1-2 INCHES... BUT THE RIDE WILL MORE THAN MAKE UP FOR IT... AND YOU WILL FIND A MEDIUM ONCE ON THE BIKE AND YOU BREAK IT IN.....SO SAFETY IS A LITTLE OF AN ISSUE WITH VIBRATION AND HAVING TO AJUST HANDS AND ARMS ALOT TO MINIMIZE THE SLEEPY FEELING IN THE ARMS AND FINGERS.... SO I HOPE THAT HELPS ... ENJOY WHAT YA RIDING !!!  

5'5" is fine...don't lower it!

if anything just slice a little foam out of your seat. but you should be fine.  

You shouldn't have any need to lower the bike at all.  I ride with a gal friend of mine that has a new Gixxer 600 and is probably about two inches shorter than you.  She didn't need to lower it at all.