You wouldn't get a stronger ring for this, you'd only trade 3 cerberus 15* rings to 2 tradeable 15*s, or 2 for one.
While soul bonding gear is important and I understand why it is done, I'd argue that an item of this much value shouldn't be totally locked on one character. I believe it to be much too big of an commitment considering their gold, IM and thus dollar value.
People playing the game on different characters is beneficial for the player base and the company in my opinion, especially if the player gears up them both. I think these rings being locked like they are make people not do that, or not get cerberus rings at all.
A 3:2 ratio is in my opinion a reasonable price to pay for the unsoul bounding. It may lead to there being a few more rings up for sell iniyially, making their prices drop. But when they are this expensive to begin with I don't think that would even be a bad thing. And the rings would also increase in demand because of this I recon, which together with a bit of time should balance things out nicely.
Be warned of typos, wrote this on my phone
Edited by Precrush, 25 June 2016 - 02:15 AM.