I've had the best luck with Philips lamps.
Some of the old fixtures from the 70's are so tight that you almost break the tubes replacing them - most often the ends break.
A little trick that has worked for me in the past is: if a new lamp doesn't work, remove it, turn it end for end and replace it. Don't ask me why, but after doing that the lamps will fire for me 50% of the time.
