It will take lot of time to become a Jr. Member due to the limit of 360 sec limitation.
I bet 0.01BTC
if you reach 15 activity, you're waiting time will only be 72 seconds. So i guess it is not much of a problem
But it will still take lot of effort to make it full member and after posting nearly 100 posts it value will go to 0.05+ so buying it for 0.06 is a foolish thing
The good thing for the buyer is he dont need to wait 4 months from newbie to full member to participate in a sig campaign. So basically buying a full member account is the best thing for users that dont have one but like to join a sig camp. Posting 100 post is i think much easier than waiting for 4 months