MG will work but you`ll have a hard time flushing or feeding flowering nutes but on a budget it`s cool
The only reasons to take away any lights during flower are 1, heat 2, cost`s 3, stress 4 they space shuttle can see your grow ! lol
The flowering part of weed works via red light trigger it needs to get a lot of red light to trigger hormones but then they have to be gone for something like 10 hours min for most plants to flower 12 hours of dark manages to trigger off most plants
Hence 12/12 for flowering
If there`s not enough red the plant will not flower hence veg lights have more blue
But you can veg under red strong light fine
Just like when you flower there`s no need to take away any 5700k light and replace it with 2700k if you can afford to just add some more 2700k bulbs and run the 5700k`s too then you will get better results as you have more light but.............
if you had 6 x 5700k 40w cfl`s on one plant then adding 6 x 2700k 40w cfl`s to the grow would add 240w to your power consumption and you would not yield loads more from spending this extra power
If you had used that much to veg a plant then I would add the 6 x 2700k 40w cfl`s and maybe keep 2 of the 5700k`s on the plant
Light is light plants use red and blue the best and red is what you need to make a plant flower but that does not mean that during flowering blue light is not used at all
In fact the only thing plants can use better then blue is red hence why led lights use blue and red.
You might even find that a 630nm led 10w to 50w added to your cfl during flowering really helps out.
Lighting is something I could go on and on about all day tbh but a 600w hps is your best bet for bang for buck
Led`s are the coolest
CFL`s are cheap and emit uv I personally like uv in flowering
plasma is expensive as hell but very close to sun light with good output
and induction lights are kind`a like if hps and cfl`s had a baby really the 200w one I use as a work light seams like it would do the job of a 400w hps I just hear most of them need a little red boost to flower with that`s ok red led`s cost almost nothing lol