Re: No Pneumatics?
 

This is the cutter we use. It's an SMC branded TK-3. From experience it is more reliable than the ones posted above and locks closed after use for safety. I have no problem keeping this thing in my pocket.

To touch on the OP: Our team uses pneumatics when they seem to be the best solution for the job. It turns out that we have ended up using them every year except 2009 (Lunacy). They work well for us this year due to a lot of binary movement designs (Shooter up/down, 10 point hang up/down, load disc, etc.) and justified the weight of the pneumatic system.

It is not out of the question to design a system without an onboard compressor. This can save quite a bit of weight and make a single actuator for one purpose worth it.

Basically, there are many correct solutions. Use what works best for you in the situation.

Something else I've noticed is that quite a few teams stack all of the required high pressure side parts (pressure switch, vent plug, etc) on a long chain of brass blocks. This is very heavy and many of these parts can be piggybacked on other required parts to save weight.

Re: No Pneumatics?
 

Plastic manifolds are another really nice way to reduce the weight of a pneumatics system