Best kept secrets in tele lenses?

I own both lenses. Initially, when I just entered m4/3 in July 2011 I bought 45-200mm as a telephoto lens. After that, (I think in November 2011) I got 40-150mm on the same temporary discount it is now, for $100, and for now I keep both.

I keep both only because right now I don't want to spend extra $300+ to replace 45-200mm with zoom ending at 300mm. I think, many people will eventually want 300mm and 45-200mm is just a temporary solution until 300mm becomes affordable.

As for 45-200mm vs 40-150mm. With 45-200mm you approximately get as longer reach as 200mm vs 150mm FL tells. There are tricks with both lenses for longest reach. Oly 40-150 needs to be stopped down to F8 for better sharpness at 150mm. Pana 45-200mm is slightly better than Oly in 120-147mm range wide open. Then, after 144-147mm Pana starts to degrade and needs to be stopped down, at least my copy does.

In the end, at 150mm, they look similar at F8, but Pana is slightly better wide open at 150mm comparing to Oly at 150mm F5.6.

Then, for longer reach at 200mm you may have to close 45-200mm aperture to F10 for optimal sharpness at long focus distances. It may be OK for shorter focus distances wide open. Complicated stuff, I know.

What's not complicated is that Oly 40-150mm is definitely superior to Pana 45-200mm in 40-80mm range. That's why Pana 45-200mm is only a temporary solution on the way to longer FL. I keep 45-200mm only for cases when I need longer autofocus length, otherwise I would choose 40-150mm any time.