If you are getting into reloading, you will be getting a press..
I can not see $50.00 for a de-capper ONLY..You could buy a set of dies+a Universal de-cap die for that price..Bill.
If you shoot black powder cartridge's most loaders deprime right after shooting while they are still at the range. You decap and drop them in a jug of soapy water.
Brass cleanup is much easier if done asap. You don't have to worry about leaving empty cases in the trunk of your car and pull them out days later and the dreaded green moss has taken over and in some cases ruined your sometimes very expensive brass.
I have seen a few Shooters using Harvey's and I have never heard any complaints. For the money it looks like a good deal.
I use a Meacham ' Pope ' style, its what was available when I needed one.
It's a capper / decapper and it uses shell holders.
Somewhere I still have a Lee decapper. It is basically a steel bushing with a hole in it and a properly sized punch. Not as slick as a plier type tool, but only cost about $3.00
I have one and it works great. Takes a little practice at first, but usually the only hangup is when there is too much burr left around the flash hole. I haven't adjusted it yet, from 380 to 300 mag, it works well.