I installed a pair of lithium batteries in my 95LX on April 9. I replaced them 18 grueling days later. Almost every day I checked the fuel gage and never saw a reading of less than 100%. I wondered if these batteries would last forever -- they didn't! On day 18 they went down like a one-egg pudding. [Editor's Note: Other 95LX users have reported that the Lithium batteries drop very rapidly at the end.]
Since the time I used the lithium batteries was punishing, I can confidently say they will last two to three times as long as regular alkalines. If you get the opportunity to use these batteries, keep a spare set handy since you may get little warning that they are near failure.