is this skimmer any good?

nemo, for once I will agree with you. JKJKJK ;D In all honesty, noone "needs" a skimmer. Water changes will do the trick. You have to decide whether you can dedicate yourself to those changes or not. The more water you are dealing with, the harder it is and the better off you are with a skimmer. For example: I have a 55 softie/lps tank (70 gallons total volume), a 50 gallon sps/clam tank(70 gallons total volume) a 95 gallon fowlr, and a 10 gallon nano. I wouldn't be able to keep up with these with just water changes so IMO the skimmers are way necessary. With a 29 gallon tank tho, 5 gallons/ week is very doable and would absolutely keep up with it if the load wasn't too harsh.