You're going to experience lag on a bluetooth. I have 2 MOGAs and will probably never use them again due to that. That Logitech gamepad requires no proprietary dongle to connect to a droid. It's what I use. Just a usb-to-micro usb adaptor if your tablet requires.
Depending on what operating system and emus you have, you can connect a wiimote or 360 controller. A PS3 if you want to root your device. For example: MD.emu allows you to sync a wiimote with 4.1 Operating System or less. I use it all the time on my phone and works like a champ.
I've tried all kinds of controllers and configurations. Weird how I own a wiimote, ps3, and 360 controller and not the systems.