One of my only regrets in airgunning (now completely rectified) is not discovering the Eastern European guns sooner. In many ways the British, German and Swedish guns are incredible. And the Eastern Euro guns are too, but but in a very different way. Incredibly robust build, all kinds of power available, and accurate as heck.
I still own my Red Wolfs, and have owned S510s/S500s (but I have parted with the AA guns basically for the reason of shot count). And FX's set standards in their own ways, but based on personal experience I would probably look at Maverick over a Dreamline (unless you are specifically looking for a traditional wood stocked/cylinder rifle like the Dreamline Classic).
With the announcements of new AGT models, I have been able to pick up Uragans and Vulcans recently at excellent discounts. My collection includes Standard model Uragans in .22 and .25, and a Compact in .22. And that little Uragan Compact has recently knocked the M3 Compact (also in .22) off the top of the heap for my dedicated ground squirrel guns. It comes out of its case every 2-4 weeks, and I never give a second thought as to where the first shot will hit - much to the chagrin of squirrels up at the big range, it is dead on every time. With the M3 I normally need to take 2-3 shots for zeroing before I am confident to take a shot at a pest. Still pretty good, but not Uragan good.
I am also impressed with both the Vulcan 2's and 3's, and the used V3 I bought from a fellow AGN member may actually be my most accurate .30 cal gun (or at least is right up there) against a Maverick Sniper, a Crown and an HM1000x.
You also mention the Vixen in your initial post. I've had the standard and short models, but ended up keeping the Standard (long) only. The Vixens are a bit of an outlier in the AGT range. While still being robust, they have really shed weight compared to other guns in the line-up. Plus they don't make the same power. Plenty of power for plinking and small game pesting though, and my Vixen has been bloodied. But really more fun to carry due to their light weight, and due to their lower power output they have an even smoother & pleasant shot cycle as compared to their more powerful brothers. To me, more of a fun gun than a working gun, and overall just quiet (mine is .22) and nice guns which the whole family can enjoy. Of all the Eastern Euro guns I have shot, the Vixen is probably the only one where you really have to concentrate on the proper scope as the gun is light and it can get top-heavy with the wrong optic. The weight of the other AGTs self-mitigates any top heaviness.
Of course AGT is likely not the only Eastern Euro gun you could be looking at, if you wanted to complicate matters further. Kalibrgun also makes some fantastic stuff I have experienced with their Cricket II and Tactical models. I enjoy the Leshiy Classic for what it is - well engineered, simple, small, light, robust and accurate - although I haven't tried a Leshiy 2 mostly due to so many reports of issues and lack of U.S. support. And the RTI Prophet has saved me a huge chunk of money. I got mine cheap and 'NOS' recently after the Prophet II was announced, and it has kept me from 'having to buy' an expensive American Air Arms rifle as the little Prophet can really do everything the AAA gun can. It may not be a beauty queen to some, but once again looks are only skin deep and function is what matters most to me.
Yup, the AGT guns are the real thing, as are almost all of the Eastern Euro guns these days. Don't make the mistake I made, and discover them NOW. You won't be disappointed.
This post is already too long so I'll stop here. But feel free to PM me if you want any more detailed info on these guns.
