I suppose slow in relative terms.

I find a lot of rental "muscle cars" are in base trim with unresponsive transmissions (I got a challenger, charger, mustang and thunderbird in rental over the years... Plus the above mentioned chrysler 300 ugh) .

You put gas pedal down, and 1-2 or even 3 seconds later, the 2.5 tons of metal starts doing exciting sounding things. But it doesn't have the feel of a small responsive sport car some associate with "fast". And they tend to be wobblier in corners than some non sporty hatches with differently tuned suspension. This leads to the feel of "slow" even if ostensibly they have a thunderous v8 underneath somewhere :-/