Installed a TSP cam and dual springs in my 98 Vette. First tried the Comp Cams LSx valve spring compressor. I was not able to get the tool to compress the valves straight. On the first pair of springs, I was able to put some pressure on the springs and install the keepers. On the second pair of springs no matter how many times I tried, they were too far offset to get both keepers installed. When you remove springs using this tool you can put the ribbed side of the shoe up and everything works great. When you go to install the new springs the ribbed side of the shoe must be down to have enough clearance. Turns out the ribs were too narrow causing uneven pressure on the springs. Another thing about the Comp Cams LSx tool is that the mounting surface is rounded and sits in the Valve Rocker Arm Pivot Support. I'm not a fan of this since it could possible scratch or gouge the Pivot Support.

Since the Comp Cams tool didn't work for me I purchased a TrickFlow valve spring compressor. I immediately liked that the bottom was flat and mounted directly to the cylinder head and not the Rocker Arm Pivot Support. The tool is well made and had generous clearance for the springs. Spring installation was a breeze. The same tool design is marketed under several names and I suspect that they would work equally well.

Hope this was useful.