Personaly i dont have that much time to search through each and every scanlation grp to find a new interesting manga or find the updates of those that i follow so its useful atleast for me...
for this aspect, I recommend mangatraders, you can use rss-feeds for every manga, so you get notifications as soon as a new chap is uploaded (which won't take more than a few minutes after the scanlation group released) and they show you similar mangas to the one you're reading and you get two manga summeries every week to see if you like them.
i truly like the page, it has loooots of mangas, the servers are ok and you have some good features like rss-feeds aso.
I also don't like reading manga online, cause the quality is worse and it needs more time to switch the pages (if you have a low internet connection like me...).
AND, it happens that I read a manga very often, so it's more convenient to have the manga downloaded.