This is a kinda mini-review, I'm too lazy to register and post this on HC. Take it with a grain of salt -- just because it's on the internet it doesn't mean it's true (:

Build quality for all of these pickups is great, so I will comment mostly on tone.

GFS Vintage '59
Positions tried: neck
Fairly weak pickups, but that's what they're for. What I notice the most is that there's alot of sounds that are not really tone, but rather squeaky quacky strange noises. I can't explain it any better, but I'm guessing these are not suited for modern high-gain -- however, they seem to have alot of dynamic headroom (with very little compression), and they do respond very well to how hard you pick. I tried both the chrome covered and open variant. They sound very sweet and mellow clean though (too bad I don't do clean.. ). I suspect these are actually really good, but just not made for my kind of music.

GFS Power Rails
Positions tried: neck, bridge
This are pretty damn awesome. They are especially good for deep tunings. Two of my guitars are tuned to B standard with these pickups, and it sounds really masculine and tough -- they roar like tigers (: They are also great for soloing in the neck pos, they have a really nice fat and clear tone with cool harmonics (kinda like DiMarzio Air Norton). They have quite a lot of magnetic pull though, and they are sensitive to noise.

Positions tried: neck, bridge
These are really good too! In the bridge pos, they kinda sound like a SD Distortion (SH6), including tons of harmonics, but with more bass. In the neck position they are really, really good with a high-gain amp. This video says it all: http://www.youtube.com/watch?v=5Gwk1ps-yBQ Really sweet tone! I prefer the covered variety of these.

GFS Protube/Lipstick (strat size)
Positions tried: middle (6.5k)
These sound pretty different from ordinary single-coil pickups. I like the tone though, it's big and clear. They're pretty hot compared to how they measure in resistance.

And that's it for now. I will update later as I try new pickups from GFS.

I maintain a website with music I create at http://music.printf.no/, 90% of the guitar tracks in the music is recorded with GFS pickups.

Two of my GFS equipped guitars:

Full version: http://sportsfiske.nu/foto/arkiv/23742/59695.jpg
Yamaha RGX 621D (power rails and a protube)

Full version: http://sportsfiske.nu/foto/arkiv/23742/59696.jpg
Jackson KE3 Pro (power rails and a fat pat)

I hope everyone is having a cool weekend!