Ordinary collanders and regular mesh stainers won't do a thing for pelletized hops, but should be OK for leaf or whole hops (little bits might still pass through).
I bought three SS china cap strainers (medium, fine, and bullion)--the pellet hops pass right through the medium and fine strainers w/o being trapped. From personal experience, you'll need the "bullion" or "extra fine" strainers. I like placing it over the fermentation bucket and running the wort from the kettle into the china cap. Most of the hot and cold break stays behind in the kettle and the strainer catches whatever escapes the kettle via the spigot or cane. No clogs and the splashing seems to aerate the wort just fine.
The fine nylon mesh screens and hop bags seem to have an even finer mesh, so if you want to trap more of the hop particles, you'll want to use that for the final screen. I often use the bullion strainer before the large nylon funnel + nylon mesh screen.
I'm curious--is there any particular reason why a sanitized nylon mesh or "paint strainer" bag over the strainer, output hose, or fermentation bucket wouldn't work for you?