Olight T20 Q5 battery options

I have the coolest wife ever! She totally surprised me and got me an Olight T20 Q5 for Christmas! She knew I wanted a light, but I was totally impressed that she figured out the one I wanted. It's my first Cree light, and I'm blown away!

I have a couple Duracell primaries in it for now, but I was thinking about getting rechargeables, and need some advice.

After looking around the forum, it seems like AW's 750mAh RCR123s are the most popular among a lot of people here.

However, I've noticed a lot cheaper options on dealextreme. The Trustfire RCR123s are $4.90 for a pair, and I could get a DSD charger for $6.64.

Another good option looks like the Tenergy 3.0v 900mAh batteries from Battery Junction. Would they last much longer than AW's 750mAh ones? Would the 3.0 voltage make much of a difference when compared to the 3.7 voltage in the other rechargeables?

Does anyone have any input on how these batteries compare to each other? I'm assuming the DX batteries will probably have the least capacity and worst quality control. Do I have to worry about any of them fitting into my T20?

Another option looked like powering the light with a single 17670 3.7v battery. How would runtimes compare...and would the light function on all five levels of brightness? It seems a little more iffy that the light will work with just one battery.

Thanks for any input!

Is this the right forum to post this type of question in? Or would the "batteries included" forum be more appropriate?

Jos....
Any 3.0 volt or 3.7 volt will work fine in this light. I have one too. Not any difference in output...it's well regulated. The 17650 will not fit yet. They new T-20 model will handle the 17650. I have the Tenergy 900 and the cheap 3.7 volt DX unprotected batteries. Both work great. Not too much diff in run time. The AW batteries are considered the best. If you have rechargeables....A little difference in run time shouldn't matter.
I also just got a set of the 3.0 volt life PO batteries from Battery Junction. They also work great, but I'm not sure yet about runtime. They have a safe chemistry.

Thanks, Lighthouse. Do you know if the DX protected batteries will fit the T20?