Firmware 3.1 worst update ever iPhone 3G

I started liking apple since I was so naïve to think apple engineers know how to build decent software and firmware.
Since Firmware 3.1 I regred these thoughts.
Man, man, man, my iPhone doesnt react to on/pff switch (well, actually it does, AFTER 5 SECONDS), slide is slow, calling ppl is slow.
Please provide us with a rollback possibility or build a decent new firmware.
At least I learned Ill NEVER upgrade anymore untill a newer release will be given.
HP 6710b Laptop Windows Vista iPhone 3G 16 GB White