I still haven't seen any Saga Legends, but I did find and purchase all four of the Mission Series two-packs (I saw them at two different TRUs).
I certainly wouldn't want this kind of figure to replace the highly detailed, super-articulated figures we've been accustomed to over the last handful of years, but there is definitely a certain charm to these figures, and some of them even trump their collector-focused counterparts in a few ways. At any rate, paying $10 for two figures feels nice after the constant price increases.
The plastic definitely feels different - the easiest point of comparison is obviously on the Battle Droids, and it feels a little cheaper, maybe, than the figures we're used to. The packaging artwork is surprisingly cool in person, IMO. This line also features a new style of packaging, with the bubble only glued to the card along the top - once you break that seal, the bubble and tray slide up with ease. (Three of my sets were glued tightly, but one set seemed a little looser.)
The Seeker Droid is pretty cool, though I would have preferred it to have had more details and parts (like the antenna). Vader doesn't look too great (I opened the Black Series figures I got at the same time, and that Vader is pretty awesome), and especially his helmet looks tiny, but as a vintage-style toy he works. He's the same height as the Evolutions body figures.
I actually quite like the Anakin figure, even with the poor-looking leg articulation. He doesn't look too bad compared to the Black Series AOTC Anakin - and they're essentially the same height, though this one is paler than the TBS version. But the likeness is far better here than on TBS Anakin.
Jango just feels like he's too "wide" to me, which is mainly due to the helmet and jetpack. It's really not too shabby though, and it's nice to get a Jango who isn't lilac. Unlike what early photos showed, he does include two blasters.
I also like the clones for what they are. The helmets are too small - sizewise, Hasbro should probably split the difference between these guys and the TVS/TBS ROTS trooper helmets. The eyeholes look small compared to previous versions, but I could definitely see these being successful as diorama fodder. I didn't compare to all previous versions, but the 501st Trooper is definitely lighter in color than the TVC figure. The straight arms obviously don't lend themselves to many action poses, but just standing at attention, they look good. They're a little shorter than the TVC mold.
The aforementioned Battle Droids, despite feeling like an obviously different plastic to the myriad previous releases, really aren't bad. I've seen online how people are having issues keeping them standing, and while I didn't have them set up standing for very long, I didn't have any problems - they stood as well as, if not better than, the other releases of this mold.