I'd put myself as intermediate. I have been here for a long time but have always been more into the photography and general awesomeness of lasers as opposed to the technical side so never really went to advanced.
Advanced. While I think my extensive knowledge is a bit excessive for Advanced, it's not where I would be comfortably stating Expert. I think Bloom, UK, and a few others are in similar positions. The higher tiers are a bit vague for this poll since no one knows EVERYTHING about ALL lasers. Well, except for Dr Sam. I think he'd fit in fine there.
I'd say advanced. I've held my own in a university lab, as long as they keep the equations out of the topic. Gas is the one realm that I can really talk for days, though I am by far nowhere near "expert".
Hell ... I almost feel boastful claiming "advanced".
Though there's the added benefit of starting with gas I'd say. On a fundamental level, all lasers are the same. There's a pump source, whether electrical, light, heat, etc. There's a gain medium excited by this source. Again, whether that's gas, a crystalline lattice doped with some rare earth metal, or a semiconductor. Then there are mirrors to create the cavity, gathering the output light, allowing it to resonate and "gain", and releasing a percentage of this light in a coherent beam.
On a basic level, they're all the same. Pump, gain medium, mirrors. The great thing about gas is that you can, with ease, manipulate the cavity to do whatever you want. I say "with ease" as in it is very easy to change something. Not that it's easy to change from one working system, to another, it's just easy to make changes. Making the right changes is the challenge.
So I guess, yes, I'd say advanced. Though again, I do not want to sound boastful or anything. I still have TONS to learn. If anything, the past week and unaligned 532nm cavity in front of me can attest to that. As can anyone I have skyped with over the same period.
On the bright side, I can now identify 1064nm over 808nm ... Soo ... there's that.
something between beginner and Intermediate i guess, i dont plan on building my own lasers and that so i doubt i extend my knowledge that much, i know the basics etc for now which is enough for me to have fun.