Have not tried one, but have several red dots. That one looks good for the money. Also see in the comments where a guy with a 45-70 was unable to kill one, which is good.
The Bushnell TRS-25 is 97.99 at Optics Planet, so might take a look at that one. It also comes with an integrated Picatinney/Weaver rail mount. It's listed as "Best Rated" on Optics Planet, which is a very good place to buy, BTW.