To echo what was stated above, I've found amanos to continue eating algae, even after being in the tank for awhile. Plus they can reach all sorts of hard to get to spots which SAEs and Ottos can't get to (or won't normally go to). The LFS I like sells them for $3 per shrimp (or slightly better prices if you get more of them).
I've found Ottos and Plecs to be less than useful for algae control, except brown algae (which they devour better than anything else IME). I'd say if you can 'borrow' a small school of ottos for the initial brown algae outbreak in a new tank, and then return them after it's over, that would be best.
SAEs are pretty good at nibbling various types of algae off plants. I like having one in my 20 gal.
Large ramshorn snails kinda fall into the same niche as SAEs and clean the glass. They're really quick for snails, and with a few large ones, the population stays under control (since the little ones can't get enough food to grow). They also eat unsightly dying plant parts. I know they're considered a pest snail by most, but I like mine. I would like to experiment with other types of snails.
My guppy population (and from googling, other livebearers too), also take random nips of algae. They don't seem to do nearly as much as dedicated algae eaters, however.