Lipo batteries can sit for a very long time while experiencing very little discharge. So to answer your question, lipo batteries, as long as they are stored properly will be fine I unused. As far a battery quality-probably going to get flamed- since I have owned about 14 lipo's, the most recent being the nanotech batteries from hobbycity are awesome and very affordable. I recently purchased 2 2s 6000mah batteries 25-50c and 2 3s 5000mah 25-50c-all softpack delivered from China in 4 days for less than 200$. My team Orion hardcase 3s 3800mah 45c batteries coated 140$ a piece. In my opinion the hobbycity furniture batteries are not quite as punchy but a better overall value.