I've considered the 90 cm ES versions for the 70 Gallon I have, finding T5 bulbs is troublesome for the 39W and the RBG mix works, but I like some more user friendly controls.
Radion Ecotech has a FW light where you can control and adjust lights and intensities, and colors.................
350$ per unit vs about 275$ for the more spread out Twinstar in the USA. But the Radio put out more light, but with less evenness. Trade off.
Location Location Location
LED
Ecotech Radion XR15FW Pro G4 $465
And then mount in some fashion
RMS Hanging Kit $60
OR
RMS-15 Mounting Arm $123
OR
RMS Mounting System (better light placement - more suitable for rectangular vs cube tanks) $182
BUT I still need the rails
RMS Track 30.5inch $73
Ecotech Reeflink $150
(Apex goes up rather $$)
Then I've a 90cm x 45cm tank so will actually need 2 XR15FW for more consistent coverage
(note these are best price rates & not my local)
In the end I decided to give Ecotech a miss (especially as they were somewhat evasive regards light tech inquiries)
I'm waiting to see what Twinstar might offer - if they arrive