I have those same Galilio batteries. I am not impressed.
I bought 2 batteries on ebay (the $10 for 2 batteries plus charger deal). They are the black batteries. I have been using them since shortly after I bought my Evo.
A while back I decided to get a couple more. I saw the Galilio batteries and figured I would give them a try. They were supposed to be 2000 mAh so I figured they would last longer than the 4 hours I get from the cheaper black batteries (I'm a heavy user and my 4G stays on constantly).
For starters, the Galilio batteries don't have the little "lip" that makes it easy to pull them out of the phone. And the charger is identical to the one that comes with cheaper black batteries.
I have noticed no difference in performance. I get the same 4 hours out of the Galilio batteries that I get from the cheaper black ones. I think the 2000 mAh is a lie. Physically they are the same size as the black ones (and stock red one) only they are missing the little lip to pull them out. Oh, and I think it takes just as long (or even longer) to charge them as it does to run them down. It takes like 4-5 hours to charge them, and around 4 hours for me to run them down.
I am just about to buy a coupe more batteries to leave in my cars as spares, and I am getting the cheaper black ones.
To put it in perspective, I leave 2 batteries at work (the galilios), and I have 4 black ones at home plus the red stock battery. I usually have 1 or 2 of the black batteries with me at all times. I leave my 4G on constantly and when my battery dies (after 4 hours on all of them) I just switch to a new battery.
Save yourself the money and get the black batteries. They are half the price, the performance (and charger) is identical to the galilios, and they have the lip making them easier to remove form the phone.
Oh yeah, if anyone has a suggestion for a "pouch" to carry these things in I would love to hear it.