I understand what you are saying about lag, but that was in the old days with heavy materials. Many compressors are using lighter alloys.

I saw a system installed on the Powerblock and the last thing they said on the episode was "You were asking about lag, what lag? Then he punched it
and he was gone.

Here is their claim:

With the turbo so far back, don't you get a lot of turbo lag?

No, our turbochargers are sized to operate at this remote location. Just like any turbocharger, once the turbo is up to temperature and in the rpm range for which it was designed to operate. The boost comes on hard and fast. All of our systems will produce full boost below 3000 rpm.
If you were to take a conventional turbo and place it at the rear, you would have lots of lag and consequently, our turbo wouldn't work properly if mounted up front.

Isn't there a huge pressure drop with such long intake tubes?

No, if the pipes were 100' long there would be but we are only talking a few extra feet and we size the charge air tubing so that it will flow without a large pressure drop. We typically will get about 1/4 to 3/4 lb difference between the turbo compressor and the intake manifold, which is nothing compared to the pressure drop across an intercooler. With high boost applications, these numbers will increase slightly.