Is the G105, a basic keyboard with backlit?
What is the difference between G105 & G110?
How is G510 as compared to G110?
Don't want to go with Razer.
Basically, G105 was introduced by Logitech as a Call of Duty flavored keyboard. It is a full keyboard with 6 macro keys and backlit keys. The keyboard is now marketed without the CoD logo, and with blue lights, instead of green.
It is pretty much a younger brother to G110, with most of the core functionality intact - the differences being in backlight options (G110 has more colors, G105 has blue light with variable intensity). G110 has 12 macro keys compared to 6 on G105.
While I don't own a G105 personally, one of my friends has it. The feel of the keys is okay - but frankly, after using K60, membranes just feel wrong. I found the backlight intensity okay, but my friend often gripes about it - so it comes down to personal taste I guess.
Both G510 and G110 are both good keyboards. G110 is solid bang for the buck. However, I find the G510 too gawdy and gimmicky. My personal opinion is that spending anything above 4K on a membrane keyboard is not worth it. Better to spend a bit more and get a mechanical keyboard.