Extreme 5th vs 1ST generation is SLOWER. Why?

I know how subjective the AE hardware/software issues seem to be here but just trying to troubleshoot

my particular network issue and could really use some help.

I ran a 1st Gen Extreme - with firmware 7.4.2 for years in my home/office/studio network and don't recall any

lag or slow resolve of browser pages but browsers/web connectivity, as well as wifi distance, is markedly

slower after recently upgrading to a 5th Gen AE with firmware upgrade 7.6.4. I got a great refurb deal and

thought would be a great improvement and wonder why we're not seeing it?

I have Charter ISP - a DOCSIS modem 3.0 ethernet-cabled to the Extreme router. From there, several ethernet

connected desktops, and several wireless IMacs and Minis with OSX 10.6.8 on the majority of them.

I didn't even move to Leopard (or SL) from 10.4.11 til about a year ago and i swear everything was faster under

Tiger.

I've studied threads about configuring "5G" and so forth. That doesn't seem to have resolved things but rather

seems that wifi distance/sig. strength is reduced to laptops, Blackberry/IPhone etc - even in line of sight of the

Extreme.

I just want my speed back, and am even considering reverting to the 1st generation to see if for whatever reason,

it might be an improvement.

Any thoughts on what i can try to optimize this? Is there still some question about firmware? Is 5G-Only maybe

making things worse than better? Try another configuration based on machines i'm using? All up 'in the air' for me.

Thanks for your time,

Mike