is it worth changing my bulb?

I'm running a 450 hps & have been since i turned to 12 / 12 (5 weeks ago). When i bought my kit (I'm a first timer) it came with a 600 dual spectrum. I had issues with high temps (90f - 100f) at the beginning so used cfls for veg stage. Since then i've improved my ventilation and temps are between 75f - 80f. Will the 600 watt dual spectrum bulb increase my potency / yield in these last 3 - 4 weeks?

I've attached some images of the ladies, feedback of any type gladly recieved.
Attachment 277730Attachment 277729Attachment 277731Attachment 277734

What are the dimensions of your room?
What are the lumens of the 450w? 600w?

apologies. my noobness is shining through...

HPS 55000 lumens (its a 400watt not a 450)
Dual 90000 lumens
tent - 1.8m x 1.8m x 2m

looking at these numbers it seems painfully obvious!!

i think its a no brainer that adding more light should increase the overall size and density of ur buds when finished. More lumens the better. The only issue that becomes when switching on that 600 watt is heat, period. As long as you have a cool fresh source of intake are and vent it accordingly it should be great. By the way man fantastic looking plants you got there. just dont make the rookie mistake and chop them hella early. let them hairs get nice and brown.

YES

Using the 600 might be the best thing to do, but there's probably nothing wrong with the 450 either. Why don't you discuss more of your soil and how you fert. People could learn from this.
That space is really too small because they might double in size in 3 weeks. This plant continues to grow in flowering.