You need to keep the gear on for the effect to stay on, but you CAN switch in and out of gear as you please to TP and WS. Personally when im using my Polearm on SAM i will only TP in the feet (Nobushi Kyahan) and macro in the other two pieces when i Penta Thrust....works a treat and is much more powerful than any other SAM Polearm setup without riceballs. Even tonosama balls are fine, you don't need shogun to be effective, although these things are like tonosama balls on steroids =)
I'm extremely surprised these aren't used more often with rice ball equipment. Though I suppose people find +accuracy more attractive? I don't know, but 15% double attack sounds awesome.
You are also forgetting that this would give +90 defense as well with the 3 enhances riceballs peices. thats pretty sweet.
I have a question though.
Do you need keep the equipment on while the entire food is in effect? Or can you take off the enhancement equipment after you used the riceball and still keep the enhanced effect?