My new engine has a brand new set of BD10s, having never driven a cossie with these in, what they like

Been told there propper laggy but would like to know from people with experience.

Iv been in a cossie with a BD10 Exhaust and to be honest didnt really feel any difference.

Can i have your opinions please.

I will take them out if no use and flog them.

Spec is

T34 with 55, On 55lb Blacks, Enlarged Exhaust ports and Iskys if that helps