Hello, Jenger, and welcome to the CCF web site!

I have made several purchases from
APMEX and they are a pretty good place to buy. One of their real strengths is the variety of US 90% silver coins they sell. They have multiple grades as well, so if you prefer a particular grade, they are likely to have it. I just got some gorgeous US proof 90% silver
Statehood Quarters from them at a price that was below their Washington circulated quarters. The mirror-like finish on the statehood proofs is dazzling and I plan to get some more of those while prices are low.
APMEX charges a little more for shipping than some other on-line vendors, so they aren't the best place from which to buy just a few coins. It's a lot more painful to spend $25 on shipping a $100 order than it is on a $5000 order, for example. Yes, it is the same $25 but the shipping cost per oz. is way high on small orders.
Other on-line vendors that have done well for me are Provident Metals and SilverTowne. Provident has cheaper shipping than
APMEX, although both ship discreetly and in strong cardboard boxes with the coins, bars, or rounds inside plastic tubes wrapped in bubble wrap to protect them in shipping.
I like the SilverTowne "donkey bars" in the 5-oz. size. They are very well made, a solid 5 oz. of .999 silver, look great, are protected by a nice plastic wrapper, have individual serial numbers, and have a cool motif of a miner and his mule. They are often attractively priced as well. Free shipping on Internet orders is also offered sometimes.