yes, lag can be an issue for any setup, depending on the size of the turbine housing and wheel. hybrids are often implemented to minimize this condition. and when Porsche offers an absolutely zero-lag setup with power available at any moment, at any point in the powerband, it is outright verboten for the next GTR to have even slight or remote lag.
for example, the R33GTR is reknown for it's abyssmal lag, with the R34 improving upon this, but not eliminating it. the R34GTR has smaller twin ceramic turbochargers, boosting to maximum 0.4bar (about 15psi), a twin ball-bearing/water cooled unit. full boost comes on after about 3500K, which creates slight lag in stock form. but the 2007 GTR, granted it is turbo, must absolutely and should eliminate all traces of lag or the car will be an embarrassment, as this is a key feature that will be micro-analysed. lag is hereby unacceptable in the realm of supercars today.