Same here. I had an old tivo around and it uses same cable as needed by the tacx.

On your dumb trainer, can you sprint without your tire slipping?

I can hold 300w on my fluid trainer, but when I try to do a short sprint the tire slips and makes my intervals worthless.

I can on mine. Of course I'm not unleashing 1200 watts in a sprint, but really picking up the effort I don't have an issue.

I have kinetic kurt and 2 kickers, main reason I have kickers is ability to simulate climbs, in Ontario we do not have any climbs, That is the only way for me to climb for 60 minutes :)

Do you know at what wattage yours starts to slip? Is 1,100 okay but not 1,200?

No slippage issues for me. If I'm going to be doing a workout that has some sudden bursts I might tighten the tension knob an extra 1/2 turn but generally I run with the regular tension on Cycleops Fluid 2. I'm not putting out 1200 watts either, maybe 700 or 800 watts at best.