H2O coolers all leak sooner or later. The CLCs just seem to leak sooner and more frequently. Corsair changed manufacturers for the new "i" series due to so many leaks with the former non-i series.
A true open loop H2O cooling system will cool better tthan the CLCs but an entry level open loop system starts at ~$195. Since these systems offer no performance benefit other than for extreme overclocking, they are not practical for most folks and they always have the leak liability waiting to destroy expensive PC hardware.
Unless someone actually has a need for an H2O system, I highly recommend against them because the CLCs are thermally inefficient, noisy and expensive compared to a quality, highend tower cooler.
That being said, IMO people should educate themselves on the technical facts regarding coolers and other PC hardware and then buy what makes them happy. It's your money and your decision. As an educated consumer at least you know what to expect without all of the hype and fanboism that is often used to sell inferior CLCs.
In the OP's case if he didn't already have the H70 he'd be wise to just buy a quality, reliable HSF and be done with it. But due to the fact he already has an H70 it's worth giving it a try to see if it has enough capacity for his use. He'll still always have the leak liability but he seems willing to accept that risk, so he's got nothing to lose by trying it on the FX-8350.
I definitely would NOT recommend an expensive open loop H2O system to anyone who doesn't plan on extreme overclocking with a chiller. It's pretty pointless when for $70 you can have a quality HSF that provides all the cooling necessary for an 8-core FX CPU and zero water leak liability.
Building a reliable PC involves more than just assembling the parts. You need to be able to configure all of the BIOS settings appropriately. This can be quite involved and frustrating as it can require a lot of trial and error with stress testing. It is however often the only means to get a 100% reliable PC.