I use primarily varivas which is a quality flouro tippit. But I use that for trout, so I have no clue how it would work on steelhead but it might be a good idea to buy a spool and give it a shot. I've never had problems with it and it is very strong (this is the brand that I use for my 8-10X tippets especially).
My second favorite brand which is also a great tippet is rio flouroflex plus.
-kyle