That is a very pricey light to grow algae in the sump bud! And a complete waste, a bit like using a Ferrari to drive Garden refuse to the tips!
You can buy a beast of a 180 Watt Hydroponics LED (Made for plant growth) for your sump for 3k - no fancy settings but does the job like a boss.
Anyway Radion set up can be a bit finicky - some laptops just don't like talking to ecotec website. You need to down load the latest version of Java for starters and even then it doesn't always work. I can't get my laptop to talk to my Radions for love or money but a friend of mine has a laptop that talks to my lights in seconds. Costs me a lot of beer every time he comes over to fiddle but once you got the correct settings you don't need to fiddle.
The Gen 4 Pro have a much better spread of light compared to the Gen 3 Pro. I googled it and the comparison images look ok but only when you run the two side by side can you really see the difference.
I have only been running a Gen 4 for 2 weeks but I suspect it will knock the Gen 3 out the park in terms of coral growth, it just covers so much more area under intense light.
Gen 3 Pro grow SPS coral make no mistake but shadowing is a issue if you don't have enough of them but this problem applies to all LED light. I had 3 over my 180 x 70 wide tank, put a 4th one on. Much better but still not perfect, some acros still have sides that live in the shadows.
My only gripe about Radions is the price. That be said you never hear of people looking for Radion spares, my oldest one is 4 years plus, only maintenance is blowing the dust out the fan once a year.
My brother just bought some G4 Pro's in Beijing - 10k each, so we get fleeced here for them but we are a tiny market so I guess it goes with the Territory.
My parting 2 cents would be that unless you plan to be reefing long term they would probably not be worth the outlay.