The main reason IMO is not this one. The main reason is that both lasers are cheap china lasers. One of those have a lot of positive reviews and meets almost all of your needs. The other one is an unknown to us and it costs a lot more than the first one.
If you want something better than my rayfoss one, jump directly to optotronics or laserglow and forget about anything else.
Look at the Aries and the Hercules models on laserglow and at the RPLs on optotronics
Well if you are trying to burn THROUGH something rather than just making it smoke it will probably take longer than 30s if you don't have much higher than 250mW. Also depends on what you're burning through. So many possibilities lolz.
Duty cycle is important for this laser! In the last few days I built a spirograph. It was awesome with this laser BUT I forgot to keep the duty cycle, and I used the laser for over 3 min. Its power dropped to ~20-30 mW or more. It doesn't smoke the tape and doesn't light matches anymore. So keep the 1 min duty cycle if you don't want to damage this kind of laser. BTW I mailed to Faona what to do, and she was very kind. She offered me the same laser for $50, or if I ship it back to her, they repair it at material cost, about $25. I think this is a very good customer suppor, becouse I didn't keep the duty cycle, and damaged the laser. I didn't ship it back, neither bought another one, I saved money for the O-like 150 mW cute. I am waiting for that laser now.