For 70 frames, all you need is a decent quality capping fork. It doubles as a stratcher and as a plane. Use the tips to scratch out otherwise hard to reach cappings. Lay it flat and slide along the frame with the tines just barely under the cappings to lift them off, like a plane. Shapes the comb, taking out the highs and lows. Works best when the combs are warm of course.
A good fork in experienced hands will process through 70 frames quickly. Really quickly. As with many other things related to bees - just keep it simple.
The tined rollers work -OK-, kinda. They tend to load up up on honey and wax and then are not much use until you clean out every groove. If you do chose to give a roller a whirl, do not get the plastic tined style. Get the roller that has the largest drum and longest steel tines that you can find.
Hope that helps!