After doing a bit of research it sure seems to me that the Time-Sert is the clear choice for a more full-proof 'permanent" fix. The only advantage to a Helicoil I found, is that it is cheaper. Being in the industry for a little while I have seen time and time again, that cheaper is never better. Do not cut corners, no matter what you are talking about. Tools for purchase, procedures, products etc. Cheaper tools are cheaper for a reason, they suck and won't last.
So breaking the two methods down, The Time-Sert is kit that comes with the proper size drill bit to get the old threads cleared out, a tap to make new threads, a counter bore drill to lock the insert in place, the insert itself which is what your bolt goes into, the driver that drives the insert in and lastly some oil that goes on the driver. You will be looking around $70 from what I have seen.