I went with a Virtue digital {same company makes Starkey}. I've been on my hands and knees before trying to locate my grandsons battery I dropped so the dog wouldn't get it. I'm going to start my VA paperwork pretty soon and let the next set be on them. With my rating in the Navy hearing loss was a fact of life. I was also a 13-B in the guards and had a full battery fire mission go off near me when I was asleep one night.
I'm glad now I went with BTE and not in the canals. The BTE's are about as small as I can see to deal with and I sure don't want anything deeper either.
Mine are BTE also. Brand name "Zon", I'd never heard of it before. The guy at the hearing center told me they had batteries for $5 per 8 pack but Wal-Mart had them cheaper, he gave me two 8 packs to go. The first two batteries lasted 8 days, the only time I took the hearing aids out so far was shower, sleep and hair cut.
I went over to W-M and their size 312 was $7.79 per 8 pack and the only brand they had was Eveready, it had some B.S. on the packaging about being "green", probably why they cost so much. I avoid buying any product that hypes the word green, if at all possible. I don't buy Windex any more for that reason.