I've written with an Pelikan M150 for several years, but wanted another slightly longer and wider pen to use a different colour ink with. The M150 is still writing perfectly, with only a little of the gold plating wearing thin to betray its age. So I was happy to trust the M205 would be what I wanted; it is.
This pen writes fluently and smoothly with nothing more done than a quick rinse under a tap to flush out any residual oil or particles from manufacture. The filling mechanism is effective and clean - just twist the base of the pen anticlockwise, put the nib in a bottle of ink, and twist the base clockwise to suck up the ink into the reasonably large reservoir. There's no disassembly required.
The pen is relatively short so I find it much better (though not strictly necessary) to post the cap. Once that's done it's an excellent length.
The construction is light. Transitioning from using a heavy, metal-bodied pen might be odd, but it isn't a problem I find. The feeling with very light objects is often that they may be cheaply manufactured - but there is no quality problem with this pen. I find it pleasantly light. The cap screws on, so it's unlikely to come off and cause disaster in your pocket or bag.
Pelikan nibs have always worked well for me. This pen comes with a steel nib, and so appears more understated than the gold-plated ones. However, the plating doesn't affect the writing experience, and if you want to change - it's simply a case of gripping the nib and unscrewing it from the body. You can also change the nib width, though I find the M(edium) nib perfect for average-size writing where my capital letters are ~1 cm high.
The black and silver design is quite classical and slick without ostentation. The engineering seems to be similar and just as good as Meisterstucks and the like, but significantly lighter and with less precious metal. I prefer the way the Pelikan writes.