I use a single CR-1/3N 3V battery rather than either SR44 or LR44 batteries in my Bessa R. The SR44 will likely last longer than the LR44 but are usually a bit more expensive. The CR-1/3n battery is usually very slightly more expensive ( locally, about 1.98 each for SR44--just under 4 for the two you'll need-- vs just abit above $4 for one 1/3n) than the other batteries but you only need one. I think the 1/3n will last longer than the alkaline battery but not quite as long as the silver oxide battery. I started using the single 1/3n battery mainly because it is much less "fiddly" to handle. I've been using my R as my main camera for the last 8 or 9 years and have replaced the battery about every two years.
Rob
