Any opinions?

Either. They both work, but most like the mech one because it's cheaper and easier.

The mech one does not interfere with the OBD-2 readiness - which may be important - depending on your local emissions regulations.

In an OBDII inspection state like NY, use ONLY the mechanical fix for the reason mentioned above.

I used the mechanical fix

Thanks for the input. I think I'll go with the mechanical one.

can anyone help me find the thread that shows how to do the cel fixes? I'm going to be putting on my helix up and down pipes this weekend, and I want to make sure I have everything for the cel fixes before I start. thanks

The uppipe faq has the CEL fix included within it.

For the downpipe, do a search for "mechanical fix". The topic is something like non-permanent mechanical fix or something like that. Inside there are the part numbers that you'll need for this fix. It's very, very simple.

i like the mechanical fix too. no splicing required! woot!
:D

Yeah, definitely mechanical as it's easier and completely removable without a trace. I've used it for two inspections now in NC with no problems...ymmv.

Mechanical fix wouldn't work on my Perrin downpipe(not enough clearance between o2 and bottom of car). I had to use EcuTek to get rid of the check engine light.

^
That's fine as long as you're not in a state that does OBDII inspections. Just having the Ecutek kill the CEL does not mean the readiness tests are complete, so you'd still have a problem with inspection. As long as your state doesn't do OBDII scans, this won't be an issue.