Well I do have a 100 watt and I can not imagine going down in power. It does work so much quicker. I also have a 35 watt and almost never use it.
I had a big job not long ago for a large order of signs. With the 100 watt They took around 5 minutes each, With the 35 watt they took about 18 minutes each. Big differance
But I am not really comparing apples to apples. The 35 watt rasters completely across the sign where as the 100 watt only engraves where it needs to. So that really makes a big differance in time.
If I was in the market for a nother co2 laser, I still think I would go with the higher power. I have 2 differant people trying to sell me their lasers. One is a 25 watt, I could probably get it for around $4500 and the other is a 35 watt. I could probably get it for around $6000. I have the money to buy them both. But I do not have the buisness to justify 4 lasers.
On the other hand I am seriously considering Epilogs 50 watt Fibermark for marking metals. I get a lot of calls to mark aluminum, I can do it using the lmm14 but it is a hit and miss process. I am never quite sure if it will work or not. I would like to do it and know with out a doubt it will work the first time every time.