I trim my dogs nails myself - they used to fidget at first but are used to it now - i usually give them a chew stick to keep em occupied - I do little and often - worst ones to get to are the dew claws

Once you've got them, you've got them - I use mine on the indoor cats claws (she can't retract them and used to get stuck on the carpet!!)
and also on the rabbits - so have had my moneys worth