I used an Eheim feeder for vacations on my freshwater tank and it worked well. I also have an apex feeder I use on the salt. They both work the same as far as putting food in and adjusting the amount fed. The apex is noisy (but that is not a concern for me), and a bit of a pain in the a** to pull the drum off to refill it (I always feel like I am going to bust it pulling it off with the amount of force required). I bought the apex feeder partly because it saved me one outlet on my apex "energybar", to use for something else. The feeder runs off a usb style cable from the apex controller...and I have a variety of programming options for the feed (return pump off, skimmer off, circ pumps on....delay 60 sec, feed, wait 10 min start return, wait another 10, start skimmer, etc).
Cheers!