If you already have a kit lens which are pretty good as is, I would get the Olympus 40-150mm which can be gotten very cheap at around $100 - $150.00 and that'll give you the longer reach for wildlife and also portraits.
If you need something faster you could add the Sigma 19mm 2.8 or any legacy lens which together will cost you the same or less then the 20mm by itself.
So for about $300.00 to $350.00 you can get coverage from 14 to 150 plus a relatively fast 19mm lens.
That is if your on a tight budget if not well then get anything you like

A lot of contradictory advice here. Before you can make sense of it you need to actually use different focal lengths, for example off your kit lens, paying close attention to what you can get in the frame.

Those saying the 14mm is wide: yes, but not particularly wide. After all, it's equivalent to 28mm FF FOV, which was a pretty standard walk-around lens for some shooters. To get anything wide enough for interiors in Europe, you need the 9mm zoom. But then you have to worry about light. This is one case where a larger format camera has advantages that cannot be overcome.

I find the Panasonic to be a superb general-purpose lens, but I don't really consider it too wide. It is quite limiting for interiors. It's cheap, good, and fast, however.

I almost never use my Panasonic 20mm. It's too in between for me and I never liked the 30-50mm equivalent FOV much. YMMV.

Something like the 45mm would be fantastic and would give you great DOF control compared with your kit zoom. But only if you are particular to portraits and hunting for details.

Otherwise Jorg above has very practical advice.

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Of course I was not trying to imply otherwise, else I would not have mentioned the ND filters (the only real purpose of which in this context is to permit use of faster apertures). A fast lens might always be preferable but is not always necessary. And this would tend to be the case in a sunny outdoor environment. If you only get one lens inevitably you must compromise.

Living in Ireland, I can assure you that all my lenses must be fast!

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I took my GF1 to Cuba and found the P20 and P14-45 to be great.

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Panasonic GF1, Panasonic 20mm f1.7, Panasonic 14-45mm, Hexanon 200mm f3.5, Hexanon 135mm f3.2, Hexanon 50mm f1.7, Hexanon 40mm f1.8, Hexanon 28mm f3.5, Quarry Optics 28mm f2.8 Macro

Here's what I wanna do... I'm about to order an E-PL1 but I asked the seller to switch the MKII kit lens for Panny 14-45mm kit lens. I can still change that if I want, but I've read that Panny is better... Any advice here? I can also ask the seller to equip my E-PL1 with MKII R version of Olly's kit lens.

Here's a note from Head-to-Head Reviews:

However, when pitted Head-to-Head, the Panasonic lens is the stronger performer, while Olympus’s M.Zuiko lens more effectively realizes the benefits of the compact format.

+ it does have Image Stabilization, so when combined with Olly E-PL1's body stabilization it should give me better results, right?

It's one, or the other, but not both on image stabilization.

oh... so it won't give me any advantage...

any other reason why I should take the 14-45mm instead of 14-42mm?

an extra 3mm - size IS everything

Plus look at the results in this thread A Walk Around Bishop Hill

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Panasonic GF1, Panasonic 20mm f1.7, Panasonic 14-45mm, Hexanon 200mm f3.5, Hexanon 135mm f3.2, Hexanon 50mm f1.7, Hexanon 40mm f1.8, Hexanon 28mm f3.5, Quarry Optics 28mm f2.8 Macro

haha, I'm not sure if that's not an irony but anyway... I can ask the seller to equip my E-PL1 with either Olly MKII lens, Olly MKII R lens or Panny 14-45 but I want to make sure that I choose the best kit lens and get vivid colors in the pics. Are these kit lenses really much different?

Sorry for the double post!

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