For what it's worth, I got a clown pleco for my 29g and I love it. I'd stay away from the CAE, though -- I gather they can get aggressive as they age but have no personal experience.
Why don't you look at otos as an option. They also go by the name dwarf sucker catfish. Before you get these fish they like a well-established aquarium. You will also need to feed your algae eater foods such as algae wafers and a variety of vegetables to choose from. They cannot survive just on algae alone.
Look into farlowellas. there are some large flases in the ones you are debating. the algea eater will be very aggresive when they are large. It is common for them to develope a taste for fish and actually try to attach themeselves to your fish later in life.
the pleco will usually grow excessively large, very territorial and aggresive (especialy if the are crowded and a 30 gallon would not be a good idea for a growing non-dwarf pleco), and all plecos, dwarf or not will get lazy and produce massive amounts of waste. farlowellas on the other hand only get 8-10 inches, add an interesting look to your tank, never get aggresive, are always on the glass and do not create a waste problem
The poll doesn't allow for a good comparison. "Albino pleco" could be anything from a small bristlenose to a huge Adonis. I will say that a CAE should be avoided though, especially in a 29 gallon tank.
Are you planning to buy a fish for the sole purpose of eating algae? If that is the case, then I recommend cleaning the algae by hand.