I did a strict 300 pound pound bench at 150 bodyweight.
Credible,but not incredible! 
Pretty damn good in my book! I (formerly Doriancutlerman, btw) never benched double bodyweight. In fairness to myself, I didn't flat bench regularly all that long; I started at 14 and would do some long periods of flat bench, then go through phases in which my focus was on dips and inclines, up 'til my early twenties. After that, I was mostly a Smith, dips and Hammer Strength guy, just doing intermittent cycles of flat bench for shits and giggles. I actually loved them. I'm 5'7" and barrel chested, so once I got the form down, my strength shot up very fast. I did a very low volume, moderate frequency routine and did every rep paused. I started with something close to my 10 th and worked my way down weekly. My best ever was something like
135x15
185x8
225x5
275x1-2
315x1
345x1
then 370x3, with a lighter DC-style set with 295 to failure, 15 deep breaths, again to failure, 15 more, then one last go. That was it for pecs.
Anyhow, I decided that was enough because I was taking dbol and 500mg Test E. at the time and needed to cycle off: I had stupidly let myself get upwards of 240, my bp was bad and my red cell count was through the roof. I cut out the orals, reduced the test by half, and continued to train with the semi-DC style until my diverticulitis blew up and took me out of lifting forever.
Tl,dr: don't get old! It sucks
