I currently have the Compact Top for 4 bulbs situated over my 30gallon tank (36" L x 12.5"D x 18" H). These are just my observations thus far.
Wattage
Do not use a bulb higher than 26 watts.
I didn't realize that 26 watts was the maximum and I put in a 50 watt incandescent bulb in one of the middle sockets and as soon as I flipped the switch, there was a flash and the bulb blipped out... After unplugging the compact top, I checked to make sure the bulb filament was still intact (which it was), put it back in the socket, plugged back in my compact top only to find that 1 of my switches (2 bulbs per switch) no longer works. The 2 sockets that that switch controlled are now "burned out" I assume and bulbs in those sockets are automatically on whenever the compact top is plugged in.
This doesn't create a huge hassle, just that now I need to unplug it from the wall outlet every night and plug it back in every morning.
Overheating
I currently have two 26 watt exo terra 5.0 UVB fluorescent bulbs and two 25 watt incandescent bulbs in my compact top.
7am - all 4 bulbs ON
5pm - 1 incandescent + 1 fluorescent ON (thankfully 1 of my switches still works)
So all 4 bulbs are on for at least 10 hrs a day and so far there have been no overheating issues.
Basking light
My two incandescent bulbs are 10 inches away from the basking platform and my thermometer is giving a reading of low-to-mid 80s degF.
Although the basking temperature should be around 90degF, the 2 incandescent bulbs seem to be sufficient for my 1 turtle of 2 inches.
Size
I find the 4-bulb top takes up too much room, and it leaves me with barely enough room to get my arm inside the tank. This makes in-tank adjustments (netting out excess food, fixing rocks, logs, etc.) difficult and cumbersome, unless you take the top off each time.
Final comments
If you were planning on buying this compact top to combine both your UVB lighting and your basking light in one fixture (like me), I would go another route. However since I spent $78 on this hood I feel obligated to use it to its fullest potential *sigh* Unless your basking platform is less than 4-5 inches away from the incandescent bulb, the 26 wattage issue is a major barrier if you want basking temperatues excess of 90degF.
Would I recommend? For my tank size and use, no. If I had known about all these little details, I would have just bought 2 light clamp/stand fixtures. It probably would have been cheaper, more versatile in its usage and it would definitely have taken up less space.
Hope that helps
