Diamond Bright looks to be a PebbleTec knock off, and ColorScapes is similar to the old (discontinued) 3M Color Quartz, which even 3M couldn't make a go of!
What are you trying to see in your pool? Do you want an exposed aggregate, or are you just looking for longevity? The National Plasterers Council will "require" most plaster companies to provide a 5 year bonding warranty, and life expectancy on a product is typically the other time frame noted. A one year warranty doesn't say much to me, and the seven year (read the fine print!) is more than the norm (again, 5 years is typical), but on a product that is sold to any pool guy with an account at National Pool Tile, so installation could be an issue.
See if you can get referrals from pool builders in your area as to who they use to finish their pools. If they trust a company to finish the pools they build, that is a pretty good indication of the outfit.
Draining and prepping your pool in the heat is not a problem. Plaster tends to "check crack" easier in the heat, so if you can prolong it until cooler weather you can minimize this. Of course, if you go with a stronger finish (exposed aggregate) that is not really an issue.