Modification components views please

My bike light currently runs 2x10w 6v mr11 bulbs in a single metal housing running off 6v 4.5ah sla slung off the top tube. It's pitifully dull & yellow especially when compared to my eagletec d25a2 clicky! Now, I have thought of mounting the clicky to the bars but would like to upgrade bike light if it's cheap enough.

I've found an article that mods a similar light using an xr-e r2 cree drop in rated at 117—220 lumens & replacing the reflector with 35mm reflector.
Now I want similar light to the eagletec so looking at dealex.com have come up with a 450 lumen drop in using xpg r5cree.

http://dx.com/p/ultrafire-xpe-r5-1-mode-450-lumen-smooth-aluminum-drop-in-module-121722#.UtwJpahFAiE

Two of these would be awesome I think, & should only take 1.5amps each (the light has a 3 way switch so one both or the other are on) which is slightly less draw than current 10w halogens. So the sla should be OK? Am I correct in my thinking?

Also, would the larger reflector just replace one for one the drop in reflector with no mods required? http://dx.com/p/35mm-35mm-aluminum-textured-op-reflector-for-cree-led-emitters-2-pack-14599

Thanks

No, the larger reflector won't screw on correctly. Read review by stevenlparry, 27/11/2010.

Yes, the SLA should be fine. However, this dropin should have a switching driver in it, which means it won't draw 1.5A at 6V. It should draw around 6W at any voltage, so it will be substantially less load than the halogen, while producing lots more light.

The one downside is that the dropin will need some heatsinking. It should generate around 4.5W of heat (the rest comes out as light), and that needs somewhere to go. Otherwise the LED will overheat and have a (possibly very) short life. These are generally intended to go in aluminum body lights, and the body dissipates the heat.

Also, considering the source, it's quite possible that it's considerably overrated. 450 lm (actually the datasheet says 463) is what you can get out of an R5 without overdriving it, and these low-end products rarely achieve that. The reviewer compares it to another light that's probably overrated. But that just means that your battery will last longer, and you won't have as much heat to contend with. It will still blow the doors off the halogens.

Oh, one more thing to consider. I don't think bicycle lights are regulated in most places, but if the dropins are even in the ballpark of their ratings, this is a huge amount of light to blast into the face of oncoming riders/drivers, and potentially dangerous to them (and thus to you as well). You may want to do some reading in the automotive forum before actually doing this.

Thanks for the response, I had seen that review but didn't read it fully, doh! It looks like the guy whose article I found too.
I may have to rethink as he says it isn't suitable for xpg led, only the xr-e & as you point out looks like the threads are different.
The light will be used for training on the road so only one led required at a time & can angle down, when in forest both will be on for max visibility.