I am now on my second ED50 and I have used the 16x DS, 20x MC and 13-30x MC zoom (old one with fold down eye cup). I have a Swaro ATM 80 HD as my main scope but use the Nikon as a pocket scope or travel scope. I like to use it handheld with the Grippa case or on a lightweight monopod. Here’s my take on the eyepieces:
16x DS - my favourite eyepiece. It has a wide field of view, can be easily handheld and gives a super bright image. Even though it only has the rubber ‘bra’ and no eyecup, I find it easy to use.
20 x MC - also a very good eyepiece with a wide field. Can be handheld at a push but better on a monopod
13-30x MC zoom - I hated the limited field of view as it was so hard to find the birds and it was very dark at higher mags so sold on quickly. Felt like I was looking down a narrow tunnel. Apparently the 13-40 has a similar narrow view so I’ve not felt the need to go there as I prefer the wide eyepieces.
I would like to try the 27x wide as it gets good reviews but I’m worried it may be a bit dark and I know it will be a tripod only eyepiece.