The Eheim 2217 is the older model and is not recommended because apparently its not that powerful. I had a look at the Fluval. Looks awesome. If I were you i would go for the Fluval.
Just to let you in on a couple more tips for Discus. I have 14 now in my 260 litre. Alot of guys are going to jump up and down and sideways when they read this but my view is that its NOT a problem because i do regular water changes - about 20 litres every day - and out of the 14 only 6 are just about adults. Rest are mid sized and small. So as long as I can have another tank on standby when they become bigger its not a problem for the next year or so.
What I wanted to share with you is this - instead of doing bi weekly water changes or weekly water changes of 40% etc the best is to infuse water into the tank everyday. Makes life easier and the fish are happier. Change 1 standard pail of water every day - should be around 20 litres.
With regards to syphoning the tank - this you can do one a week. No need to do it everyday. If you have a box filter inside the tank then you can rinse the sponges in the aquarium water once every two weeks. Remember to make sure that your filter is not off for too long. I usually give myself 15 minutes to get things done just so that we dont end up killing the good bacteria for want of oxygen.
Ofcourse you will need to replace the first layer of white wool weekly as this gets really dirty.
Also thing about putting in some beads - ion exchange resins mixed with activated carbon as this will make the water clearer - optional i guess - many school of thoughts o this and blackwater extract which i use once a week. 60ml.
Lastly, dont ever dump chemicals directly into the tank. Things like liquid Co2 , fertilizers etc. Always mix it in the pail of water that you are infusing into your tank!!
All the best bro