The only 12 footers I have are a couple FSC 120s rated at 1 - 4 lb line. I do have a 15 foot one piece Lamiglas I use for bank fishing sturgeon.
Yeah, I bet those FSC 120s are nice. Those are right up my alley. I have an old ultralight Fenwick/Woodstream 12 foot SH-1441 steelhead rod that I bought to retie. I took off all the wire guides (which was a chore with all the old rod finish), but I haven't taken the old handle off yet. It's a bit of a work in progress, but it'll be a great rod when I get it retied with Pac-Bay Minima high frame guides with titanium nitrite inserts.
I also have an old sweetheart 10 1/2 foot Lamiglas S-Glass blank that I traded for from an older friend of mine. He bought two blanks back in the day, tied one (which he still has) and had the other blank just sitting around all that time. Along with that rod, I also traded for a 12 foot Fenwick Blackhawk blank he had as well. If you are not familiar with that one, it was Fenwick's first graphite rod. The Blackhawk series was identical to the HMG in materials and construction, but it had an un-sanded (micro-layered) blank.
All three rods are perfect for the Great Lakes ultralight-style steelhead fishing I do with light line. The Blackhawk is a beautiful rod and the 12 foot fiberglass Fenwick will be a great one too once I get it tied. The 10 1/2 foot Lamiglas S-Glass is a honey of a rod though. You can land 10 pound trout on that thing with a 2 pound test leader. You can literally walk backwards while fighting a fish and not break the line. The fish just pulls and thrashes and the rod just loads up like an infallible shock absorber. It's insane.
Whenever I see old 10 1/2 foot or longer fiberglass and early graphite ultralight/steelhead/fly rods or blanks I always pick them up. Not to mention the ten brand new, still-in-the-bag 14' Hardy graphite blanks I bought for an insane $50 each a few years ago! Deal of a lifetime. I still have two of those blanks (still need to tie them) and my buddy has one tied, and one blank from that deal as well. Outstanding finesse steelhead float rods they are.
In regards to the old fiberglass stuff though, sadly, they don't get the attention they deserve. The 10-13 foot ones that were made back in the day are getting exceedingly rare around these parts and they either go for peanuts because the original owner sees them as "antiquated", or they go for insane money because of their rarity and past prestige. There's no in between. I'm always on the lookout for them though. Cheers.