A must have eyepiece for any serious amateur astronomer - TeleVue Nagler 31.0mm Type 5 Eyepiece EN5-31

I own a 10 f/4.7 dob. I currently own the 31mm type 5, a 17mm type 4, a 13mm type 6 and a 9mm type 6. I would have to say that looking through the 31mm is so incredible you would just have to see it on your own. I am currently looking at northern-hemisphere winter objects, so I can only comment on those, but too look at M31 (Andromeda) I can easily resolve the entire galaxy in the 31mm. With my old 25mm plossl I had no idea of the extent of the galaxy, but the 31mm shows dark dust lanes all the way out to the edge of the galaxy. I see structure in m1 (crab nebula), whereas it used to be just a fuzzy cloud with my old optics. m42 (orion nebula) is simply amazing, although I prefer the 17mm type 4 for this, because it just fits it into the field of view. For the first time ever for me, I can see greens and blues and on a very dark night two nights ago (estimated LM7 skies) I was able to see a ruddy (reddish) hue on the edge of m42 -- simply jaw-dropping. Looking at globulars is amazing as well. I love to look at m67 and the 31mm resolves it into 100's of stars. m81 and m82 are simply amazing with the 31mm, but again, I choose the 17mm for these objects because they are both just inside the field of view at a higher magnification.
It is a VERY heavy eyepiece (2.2 lbs), so if your dob doesn't have a good tensioning system, you may have problems. I own an orion xt10i, so I have no problems with the weight, but people who don't have a good tensioning system need to carefully evaluate this added weight before purchase.
The TeleVue 31mm Nagler type 5 is one of the most conveted eyepieces in the world, and I can see why. If you can afford to spend ~$600 on an eyepiece then you can't go wrong with this one. Amongst other naglers, the 31mm is an eyepiece that any serious astronomer should own!
Pros: FOV, contrast, clarity out to the edges
Cons: Weight

This review was written in the old system and had content requirements that are different than reviews written today.