OK, the T5's are here and I installed them tonight. I only bought two of the URI to try them. They cost $22 each at Premium Aquatics. I also bought 4 aquamedics, on sale for $10 ea.
The bulbs:
URI Actinic White and URI Super Actinic
Aquamedic Ocean White 10K and Ocean Blue Actinic
The color appearance as you look at the lamps:
The URI looks pink white compared to the AM which looks white/white
The URI Actinic looks purple/blue compared to the AM which looks blue/aqua blue
The color apearance as you look in the tank:
The AM pair gives a bright effect with yellowish white crisp tones in the water. The black foam had a greenish hue.
The URI pair gives a warmer purple/pink color, while tinting the black foam with purple hues.
I measured the LUX of the bulb pairs and they were comparable.
The URI pair produced 14,500 LUX
The AM combo pair prodiced 15,500 LUX
The AM blue/blue produced 14,500 LUX
As a LUX comparison, the RF 250 watt electronic ballast powering a Phoenix 14k bulb produces 31,500LUX.
All measurements taken 7" from lamps.
In general the AM pair looks crisp blue/white compared to the URI which looks purple/pink/white. In other words, the URI gives that great warm feel that is legendary on the VHO line of bulbs.
Conclusion: I plan to run these as dawn/dusk and at noon time in conjustion with the MH. The MH will run from about 9am to 5pm. The T5 will run 7am to 9am, then noon to 3pm, then 5pm to 8pm.
I will try this lighting regime for awhile. Since the T5 will be mostly viewed for its dawn/dusk feature, I decided to go with 2 AM blue bulbs and the URI Actinic white / Super Actinic. The looks gives a pretty blue/purple tint. I think in order to get a little more blueness I will purchase another URI SuperActinic. I will then run 4 lamps alternating the blue AM with actinic URI.
As a final note, the AM blue looks like a 460nm and the URI looks like a 420nm bulb, but neither lamp specifies the frequency range.
Here are a couple pics:
From L to R, URI actinci white, URI super actinic, AM Ocean blue actinic, AM Ocean white 10k