I think slicer is the handle on these forums, who got it done way back in 2009. Check his posts. But, to date a lot of implants are past 1 year and quite a few past 2 years. Have never heard of any complaints. I have had one for 4 months now :)
Can you share who your surgeon is ? I do think Linx is a nice option.
When you say "severe" gerd symptoms, what do you mean ? High DeMeester's ? Barrett's ?
I would certainly get esophageal manometry done to evaluate the esophagus' strength to push through the Linx barrier.
Cheers, do keep us posted.