Feature Set:  

They offer all types of licenses, including royalty free and rights restricted. Their prices are a bit on the pricey side, but the quality is better than some of the other lower ranked services. Although their prices vary according to the image type, license and usage. Some smaller images can be purchased for under $80.

They offer some helpful support topics, which other services do not offer, including a page that helps you decide what kind of resolution or size you need for your project. They also publish a comprehensive online glossary of stock photography terms.

They allow comp downloads to test your designs.

Search/Sort Options:  

Alamy's stock photos can be searched by keyword, release status and orientation.

Quality:  

For the price, the quality is acceptable; however, you may have to search through a quite a few images before you find one that is good enough for your project because there is a broad range of quality offered.

Selection:  

They offer stock images and stock illustrations, as well as some vector type images. They do not offer editorial images or assignment photographer services.

Alamy offers a huge selection of photos that can be purchased individually, no subscription required, so it would not hurt to look through this site among others if you are looking for a unique, moderately priced image.