So, i just ran the most recent (mid september) packet for a small group last night, and it went really well.

I had no plot in mind beforehand, and due to time constraints it was basically grab-pregens-and-go. Mostly they wanted to test out the combat system anyway, so it was pretty easy to find an excuse to get some action going. I tied it in to each person's background & class somewhat, pretty straightforward stuff.

The players were two vets of 3.5, and one who had never gamed before. We spent about an hour or so, covering the basics for everyone, and got started. At the player's suggestion, we did a single encounter with the Barbarian taking on some goblins and the players of the Ranger and Fighter watching to get the basic idea first. That went well enough with the Barbarian one-shotting the goblins and no hits received in return. Loaner dice for the DM.

Anyway, jumping the other two in against some beefier goblins worked well later and all three had a great time with the mechanics and storytelling. We told a story rather than having it get interrupted by fights or rules lookups, which was great for all concerned. I'm pretty much an improv style DM at this point, and 4E was nice for enabling that. This version worked quite well for that too. Players kept things moving, and we fed off the storytelling angle, rather than mechanical mastery. A couple characters got hit once each, and that was about a 50% of HP type hit. The new guy (Fighter) wisely retreated to use Second Wind, enabling the Barbarian to mop up what was left.

One ruling I made on the fly was to allow the Barbarian (on his turn) to pursue goblins that moved and hid, and destroy the foliage that they were using for cover/hiding. He'd have to spend an action clearing a given "square", but just damage rolls, no attack rolls on bushes. Elf ranger was able to detect the Goblins even through the brush, thanks to Advantage on Perception. Advantage and Disadvantage went over very well. This group had been looking for simple rules in general and this played well with them.

Afterwards the vets and I discussed the other aspects of the system, and they generally liked it very much. New guy had an easy time of it, and I think in this case at this table it was a success for us all. That's my basic report.

The first question you should ask is "did they have fun because of the DM or was it because of the system?".

This should be done because I can RP in monopoly and everyone has a great time, monopoly is not an RPG. So you want to know was the system good? And you can't really get a good answer if most or all the fun was because of the DM.

For instance the two hits you mention that take away 50% of hp. You should ask your players if they liked that as it was a pure mechanical system question rather than did you like the role play session we just had, since role play is completely independent of the system.

For the most part when I tested it out, and it was a few packets ago, the system wasn't really that fun. It was very limited in comparison to 4E and my players asked if we could go back to that.

I haven't looked at the most recent packet yet (I probably won't bother), but from what they were saying, they were going to make changes that would not be fun for me and my group.

Actually in this case, I know I can answer that the system was a big part of the fun. It had a number of things that this group had been looking for. While, yes, we can have fun with ourselves all day, but the discussion afterwards was all about what was good with the system and how it was fun and non-invasive to storytelling.

I recommend trying the newest packet. Or at least reading it before dismissing it entirely. It's night and day from the one that came out months ago, which I did not care for either, nor any other than had come out beforehand or since. This was the one that won me over. You might be surprised.

I'm sorry, I'm boycotting WotC after their treatment of me on their forums. I can't do that...