I'm a big fan of 1.2/1.4/1.8 prime lenses, for the simple fact that you have more light to work with than you do with a 2.8 zoom lens. The 2.0 aperture on this lens allows twice the amount of light as a 2.8 zoom lens to get to the sensor. I shoot a lot of indoor events and the 2.0 aperture is so much easier to shoot under these lighting conditions.It is a heavy lens, at 2lbs, but the IQ and 2.0 aperture make it worth lugging around.Despite what another reviewer stated, this lens does NOT have image stabilization. However, using it with my Sony A1 II, with in body stabilization, works great.

I found this lens to handle great. It’s SHARP and fast. I wouldn’t use this as a portrait lens as I prefer a f1.4 or 1.2 aperture but it could do if I were in a situation where I needed to carry just one lens. I am excited to put it through its paces.

I really can't say enough good things about this lens, and as a Sony shooter, I've been eagerly awaiting its release ever since Canon came out with their own 28-70mm f/2 lens. I only received my copy yesterday, but I'm already in love with it.The 28-70mm focal range is very key for flexible, ready-for-anything indoor shooting. I have quite a few GM lenses, both zoom and prime, and I pull all of them out situationally, but (until now) the lens that lived on my camera most of the time was the f/2.8 24-70mm GM ii.This 28-70 f/2 GM blows it away. The biggest gain comes in getting access to a f/2 aperture instead of f/2.8. For those who are into math, the amount of light let in is inversely proportional to the square of the f-stop. That means that the f/2 lens lets in 49/25ths as much light. In other words, this lens collects essentially twice as much light as an f/2.8. That is simply fantastic for low-light or medium-light scenarios. There's just no substitute for more light. You can shoot at lower ISO for less noise, or faster shutter speeds for less motion artifacts, or a combination of both. As an added bonus, having that wide aperture lets you get prime-like subject separation, blurring out the background for portrait-type photography.I've loved the look of the photos I've taken at f/2 on this lens. The subjects are crisp, the lack of noise is excellent, and the background is some of the creamiest, smoothest bokeh I've ever seen. However, even at f/2.8 and smaller apertures, I feel like the lens out-performs my 24-70. I haven't done a rigorous comparison--this is just a gestalt feel--but my f/2 lens seems to provide tack sharp, count-the-eyelashes clarity in a way the 24-70 didn't, and the bokeh is just beautiful.Also, the fact that this new lens adds stabilization is HUGE. I see a real, noticeable difference in handheld shots compared against my unstabalized 24-70gm. (Also, the fact that the lens is a little bit heavier can help with avoiding camera shake too, just thanks to Newton's laws and good 'ole inertia.)As far as size and weight go--and you can easily look up the exact specs on this--it isn't a small lens, but it isn't as big as you would expect. (It's both smaller and lighter than Canon's version.) In particular, it is deceptively light for its size. It's very comparable to the 135 gm lens. The f/2 is just a tiny bit larger, but it is actually a few ounces lighter.The only downside of this lens is the price. It is definitely the most expensive lens in my kit. However, it is the center slice of that "holy trinity" of zoom lenses; it is the exact focal range usually found on that first "kit lens" you get when you get your first full frame camera; it is a lens you will use A LOT. So for me, that makes it worth it.Happy shooting!For a detailed, very rigorous assessment of this lens, I highly recommend Dustin Abbott's review, which you can google. He is extremely thorough on all the equipment he reviews.