GOOD LED fixtures do not have any problems with keeping color in SPS corals - that is a myth perpetuated by people who do not have LED lighting. This myth probably stems from two key thing:
1) the problems with first generation fixtures like the Soloaris;
2) from bleaching that many people experience after switching to LED.
The First Solaris fixtures had a myriad of issues that I've read about (didn't own one), from non-standard parts, mix-and-match emitters, and lots of parts failures. PFO was also shut down by a lawsuit just as they seemed to be getting their stuff together.
The latter issue is definitely something many people who switch over to LED do not expect. If you just plonk a high-power LED fixture over your corals that were used to a specific PAR intensity, and adjust the fixture so it 'looks right', chances are that you'll cook your corals with too much light. IMO, this is one of the problems commonly encountered when people switch to LED and then complain of poor coloration. There are quite a few people on here with gorgeous LED-lit tanks. LED light is not the issue if a tank has poor SPS coloration - there is simply some underlying issue; either lack of light acclimation, LED's adjusted too high or too low, or a chemistry problem. There is a thread over in the SPS forum with some breathtaking LED-lit SPS tanks - check it out.
As with any new technology, there will be ornery neigh-sayers with no experience who will try to dissuade you from that particular technology's use. LED is no different -don't take advise from anyone who has not themselves used LED. I've used LED exclusively for 2 years now, and I admit - I am one of those people who blasted their tanks with too much light - for a long time in fact, I thought my color problems were due to the spectrum of the LED's or something like that - I bought into the hype, err - anti-hype if you will, about LED's. Then I started more carefully monitoring my parameters. I found my PO4 was higher than I had thought. Started running GFO, and colors have been improving ever since.
IMHO, if you have good color and good water params before switching to LED, you acclimate your tank to the new lights slowly and carefully, and your corals will look nearly identical after. I say nearly, because some people have reported certain species of Acro that turn slightly different color under LEDs.
What fixture did you order?