I'm sure that the SH are very good but I have never owned one so I can't really give any advice on them, but I have had my icom M71 for 5 or 6 years now and the battery life is excellent.
When away for the weekends I charge it up the Thurs night to take with me and when I get back home on the Sunday I leave the radio switched on with the volume on low to completely run the battery out.
This usually takes 3 days, then when its flat I always disconnect the battery from the unit then put it away until next time.
Doing this has kept it in tip top condition and it has served me well and always lasts like from the first day I got it.
p.s. I forgot to mention I always give it a good rinse with fresh water.