I have built a lof of custom Spinal rods. Look at beachtimerods.com if you want to see any of them. They are a lot of rod for the money. Very light weight blanks and can be kept that way with the right components. The SPM8 and the SPH78 are probably the most applicable for GT fishing.
Here are how the blanks compare to some others in the same class.
Spinal SPM8, New OTI Tuna Sniper 8' 60/80 (still in prototype phase), Black Devil 200, Synit MKII, OTI OceanXtreme 60/80
-The Spinal is the 2nd lightest in weight behind the Synit. BD was heaviest
-Spinal is fast. In between the new Sniper (slightly faster) and the Xtreme (slightly slower)
-Spinal handle section is shortest of all, making the top longer than usual. This affects travel, shipping, and handle customization
Spinal SPH78, New OTI Tuna Sniper 76XXH, Synit PE10
-Spinal has the softest tip of these and was probably the most moderate. Similar in action to the Synit
-New OTI is the fastest and had the most reserve power
-I designed this OTI blank to double for killing the will of big bluefin tuna and be more suited for large GTs
All in all, the Spinals get a good rap here in the US. They break just like any others, but Travis has a good warranty and stands behind his rods. The blanks are made overseas, but rolled here in the US. It is still a small company so they can do that. I will openly say that parts of the Spinal rods influenced my design of the new OTI Sniper line (everything in that list did). There's things I like and a few I don't, but the good definately out weighs the bad.
Good overall choice for a budget popping option. But watch for my new Tuna Snipers. Canyon Reels Australia will have them early 2012. I plan to kick some real butt in the mid-priced popping catagory!