Well i am in two right now, have them both in my Sign.
One is RF Generation, has a very large catalog of games, consoles, controllers, ever made for each consoles. What i don't like is that the % of games that they calculate is based in the total of game that you owned of all consoles, they do not have an idividual % of games per consoles.
The other ir Retro collect, after some discution and explanetion i regret of something that i wrote on my profile on that page, they have all european games and are adding recently North american games. What i like of this page is that the % of games own is calculated by consoles individualy and calculate the missing games you have in base of the games you own even it tells you how many games are left to complete your collection. You can set the page to only calculate only North american games, european or world wide, so the calculation would be exact as you whant it. As i only collect north american games it only calculate my owned / missing North american games and don't count other regions, i set it that way

What i don't like is that they are still adding North american consoles/games, so, for me they only have Nes, and Snes games, i had to add the games that i owned of PS1, Wii, N64 as european games, only the ones that exist on that regions even though they are north american, i have others that are only North american games that i coldn't add them.
So my complete list of games are on RF generation but i prefer Retro collect. Hope that retro collect keeps adding north american games and consoles as they told me, because is an excellent option