Hamsters & Grebils...?

Okay so I really have never considered getting a gerbil until now and I want to know how much and how little they're like hamsters and also which of the following is better, these are just a bunch of questions, just answer as many as you can:
1) Which is more playful/ Tamable
2) Are gerbils usually as big as Syrian hamsters or smaller like Dwarves
3) Do Gerbils have a differnt set of hind legs than hamsters
4) Is Gerils' tails a pro or con in size, pending on handling
5) Which eats more
6) IIs there a website that can list the Gerbil types
7) Are Gerbils more like Syrians all together or more like Dwafs
8) Finally, Which is better and why

I'm not planning on getting a Gerbil quite yet not to mention I wont be buying any, anytime soon, but like I said answer as many as you can...

Gerbils are nothing like hamsters. I personally think they are much better than hamsters.
Gerbils are:
1. More play full and active during the day
2. They can get larger than a Syrian hamsters
3. Their legs are the same design as a kangaroo (hench their other name ' Kangaroo Rat') so they can REALLY jump!
4. Their tails are much longer (which i prefer). but NEVER EVER hold on to the end because they have an ability to detach it!!! (natural defense)
5. They eat about the same and the same bought food;
6. http://www.egerbil.com/colours.html or http://home.wtal.de/ehr/gerbils/colors.h...
7. Neither really
8. I prefer them because they have more character and are more active during the day.

Animal carer with personal experience with numerous rodents