Is it okay/possible to interchange a 190mm rear shock for a 200mm?

Hello, and greetings,

I just bought a Diamondback Recoil FS at Costco for $350. Yea yea, I can hear it now... I didn't want to spend much money and this seems like a lot of bike for the price. I do want to upgrade some parts.

To start, I want to add a rear shock that has a lockout feature. There seems to be a greater selection of 200mm shocks. At the difference of 10mm, would it be okay for me to use a 200mm while the factory is 190mm? I'm guessing that either my frame will be slightly off angle, or if the frame's travel ends at the 190's extension, the 200mm will just be compressed a bit (reducing the shock's travel).

Also, does anyone know the difference between the Recoil and Recoil FS?

Thanks.