I have used a couple of Life hobbico packs on my receivers including 1 Pattern plane. Not running a voltage regulator. If memory serves me correct they were the 1100mah. packs. They weigh 3 ounces. instead of four ounces for a 600mah 4.8v Nicd. can't remember what the Nimh batteries weighed. Have not had any problem at all with them.
I did have to buy a different charger to charge them. I tried the hobbico charger for the life's but did not trust it.