Here's my experience using ARC Reef's Purple Helix, which more or less the same product with a different color selection.
Personally, I'm happy with the results in my tank. I'll post some photos later, but my tank currently has at least four very discernibly different hues of coralline covering the rockwork. I would argue that there is more diversity than that, but it's difficult to determine whether the more subtle color differences are the result of differing strains or just varying lighting/flow/placement conditions.
It's also plausible that some of those strains came from other sources, such as live rock or coral frags; however, the colors I've seen correlate pretty closely with those advertised on the Purple Helix bottle.
Generally speaking, there are cheaper and more accessible ways to introduce coralline algae into your system. You could acquire some well-cultured live rock from your LFS or online supplier. Another method that my LFS suggested is to find a hermit crab with an attractively colored coralline growing on its shell, introduce it to your system, then scrape its shell gently to release some of the algae into your water column (repeat as necessary).
Bottom line: If you just want coralline, there are cheaper methods that mostly just require more patience; however, if you're looking for a greater variety of coralline strains without as much searching and trial and error, ARC Reef is definitely the way to go. Overall, I'm glad I used it.
Note: If you're adding an ARC Reef culture during cycling, don't expect to see the full variety until your system has matured. Bacteria, algae and livestock all vie for most of the life-sustaining nutrients in an aquarium, and every system goes through its own tug-of-war before reaching a more stable equilibrium. My current system has now been established for about 1 year and 3 months, and I still notice new variations of coralline colors appearing from time to time as others become less dominant.
