Panasonic Leica 15mm 1.7
Been wanting this one for a while, but when I got a great deal on an Olympus 17mm 1.8, I decided to go for that one instead. I've been made aware that the 15mm is slightly sharper, but I think I prefer the 17mm FOV, and I absolutely love the focus clutch. It's the only focus by wire lens I've ever used that actually makes manual focusing enjoyable. Aperture ring is nice, sure, but I don't think I'll be making the switch.
Panasonic Lumix 42,5mm 1.7
Same here, really. I've got the Olympus, and while pretty ugly and not a great build, if focuses quickly and makes great images. Ideally I'd probably want the Lumix, but is it worth the upgrade? Probably not.
Panasonic Leica 25mm 1.4
I've borrowed this one a couple of times, and it really is a great lens. Only problem is, there's so much competition. There's the Lumix 25mm, which I have. Sure, plastic and all, but it's very cheap, very light, the image quality is more than adequate, and it certainly runs circles around my old Canon nifty fifty. Then there's the Mitakon, which at 0,95 does something quite rare, and there's the Voigtländer, which is the premium version of the same. While I'd like the Leica, I'd probably go for one of the manual lenses if I wanted another 25mm. Although, if the upcoming GX10 is weather sealed, the new PL might be worth considering.
Sigma 30mm 1.4
Another great lens I have no use for. On MFT, the focal length is just odd. I'd consider this on my Fuji were it available. Who knows, maybe one day I'll get an EOS-M or a Leica CL. I suppose there is a slight chance that my Olympus 45mm might be swapped for a Sigma 56mm.