i just picked up my cobra class 3 this last friday. i haven't stopped since i got it!!! i 'm surprised i have time to get on the computer. as far as advice, i highly recommend calling Steve at the leather machine company. i didn't know ANYTHING about sewing and less about sewing machines. Steve was very helpful in helping me with adjustments i needed to make for each job i was working on. the machine itself is very easy to use and work with. like i said, i haven't been able to stop using it, it's so easy. i completed two knife sheaths, two holster and three notebooks this weekend with it.
seriously, call Steve at the leather machine company. he will steer you in the right direction for what you need even if you don't get his machine. he's very helpful.