Are u using an olympic bar - if so the only time that would really make a differnce is wen ur stackign the weight on - when im going heavy (180kg +) I prefer to use 50kg plates - but that could just b old habit.
However I have benched at ppls houses where they have their own equipment and the bars r much shorter and lighter and I definately think it makes a difference cuz I can never bench as much in a house or garden as I do in a gym - I would say I'm 10 - 15kg weaker training on anything but an olympic bar with correct plates.
At the end of the day do what makes u feel comfortable, every 1 is different - I know ppl who cant bench as much at certain gym cuz the bench is narrower or wider - personally this doesn't bother me at all - like I say personal preference.
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