Apologies for resurrecting a long dead thread, but I thought I'd post the following update:
I'm now 40, and I'm having to cope with the realization that my eyesight will never be as good as it once was (and I used to have very strong eyes!). I still have no problem at long distances, but my eyes just don't want to focus on anything up close any more.
As such, I've started to rely on the optivisor more and more. I simply use the one magnifying lens (no need for the drop down additional ones... yet), and I flip my head back and forth like Hitchhiker's Guide to the Galaxy's Zaphod every time I need to refocus on the stuff on my desk, rather than the model in hand.
The plastic headband does get sweaty and slippery though. Thinking of gluing a strip of felt or terrycloth to the forehead portion. Might help.
For the times when I'm taking my painting on the road and don't want to carry my lamps with me, I'm considering jury rigging a LED lamp to it. Perhaps one of the ones that normally clip on to the front of a hunter's ball cap? I used to use a LED headlamp all the time for this purpose, but the two don't seem to work well together (maybe if I had a forehead like a Klingon, but I don't).
Anyway, I took a look at some of Einion's recommended forum threads on CMoN, and it seems that others are using these more and more as well (especially us old folk!). The other alternative seems to be cheap low powered reading glasses. Might have to give those a try too.
As for mine, it's still going strong. The plastic is not super durable though... it's got one or two cracks now (around the screws), and the bottom edge of the lens has been bumped by my brushes a few times when I wasn't paying attention (I now lick my brushes to sharpen the point and condition the hairs with spit mid-project... disgusting, but useful!).
Anyway, for you young guys, I advise that if you get one, use it sparingly in case it prematurely fatigues your eyes. For us old farts with already shot eyeballs, this may be the ticket to keeping up with the younger generation.
Man, I hate getting old...