Additional light - T5's or 250 watt HID?

I have a grow room that is 5 x 6 x 10 with a 600 watt HID digi ballast, and the goal is to grow as big as I can in that space with just one or two plants instead of sea of green, and I want to add additional lighting in to the garden. I was considering adding 2 4 foot X 4 T5's on each side of the wall, and placing them a couple of feet from the ground, so I can have a wall of light on both sides of the plant as it grows and allow it to fil out properly. The other option is to hang a 250 watt HID light below the canopy with no hood. I need to cut down on heat in the room, so the T5's are attractive to me for that reason, but will they penetrate well enough for the plants, or am I just fooling myself in to thinking that the side fill light with the T5's will work? Any input or suggestions are appreciated.

Th t5s as side walls will work out great. If you get units with good reflectors it will also help to reflect back your HID lighting.
Plus you can tune your spectrum with speciality tubes, Actinic blues and Pink plant tubes for a wider spectrum. Heat of course is lower than HID.
The bare bulb would work better in the center of 4 or more plants since you get 360 degrees of radiation.

The t5 fixtures will throw off more heat than you think, nothing compared to hids but i had temps in the low 90s with just my ballast turned down to 600w, a 4 bulb 4ft t5 fixture and 4 23 watt cfls. I removed the bulbs and the fixture and my temps have not reached over 79 with a 1000w hps in the hood now. In a 5x5 tent.

So if you already have heat issues than I would suggest the t5 fixtures if you are bent on having more light.

Not to double post but i still think running t5s would be a good idea and if heat is an issue just remove them, its not so much the bulbs, its the ballasts that throw the majority of the heat. I think next round im just going to do it with remote balllasts and just run the wires up and out the tent so it can sit next to my hid ballast. I have a lot of t5s and would like to use them for side lighting im just going to have to run them with the ballast outside the tent and not in the fixture.