Re: first skiis
Hiya,
IMO, buying used is a good idea for a combo set. 66" is usually "standard" ski length... so that seems normal. Big thing is to make sure the rubber of the bindings is in good shape, not ripped or starting to rip, and make sure the bindings are adjustable to your foot size. If you've got size 12 or 13's sometimes they don't go big enough.
Reality is, that I don't think it matters very much what kind of ski's they are. O'Brians are a decent name. We have a couple old sets of combos... We still regularly use old wooden plank ones. They still work. The one's in your pict are much nicer. BTW, combo's are also good for leaning how to ski on 1 ski. (that's the "combo" part) Too often someone will go and drop big $$ on a slalom ski when they don't know how to ski at all. Real slalom ski's have high rocker, high drag, and feel heavy when you're just skiing behind the boat. Sometimes they are downright hard to get up on, especially if they have a dual boots. Not for the novice. Combo ski's tend to be flatter, have less drag and not be as tiring on the hands/arms, even just going behind the boat when you're learning. And having a toe piece instead of the 2nd boot is how you should learn deep water slalom starts anyway.
I have no idea about the price, but if you got 'em for $80, that's probably a whole lot less than what they sell for in the sporting goods store.
good luck