I just got back from 2 hours at the a-cho location test.

I played it as B-Expert, with Autobomb OFF. Doesn't get much harder than that, but everyone else was playing Shot or Laser all day and I wanted to see the tougher bullet patterns. My credit ended before the first boss, but it was a fun ride. No one got to the Stage 3 boss in my time there, but it was the same 5-6 guys rotating over and over. Some were getting progressively better and even making some neat scoring patterns. I watched the runs for a good time, studying the bullet patterns.
Some things about the autobomb I noticed:
Shot starts with 3 bombs with autobomb ON or OFF, but with each death with OFF you get an extra bomb whereas with ON you only get 3 bombs per life. Laser starts with 2 bombs, and Expert with 1, progressing to 2 once you die (with OFF), but staying as 1 (with ON). Autobomb kills your entire bomb stock, and the bomb doesn't last as long as a normal bomb. I don't think there's any difference in score among ON and OFF. At least I couldn't see any difference. Most people started with ON but switched to OFF because it's actually easier that way with the extra bombs, provided you bomb at the right times. I'm also pretty sure an autobomb kills your chain, but a regular bomb doesn't. I did see some bombs that killed the chain, but the last guy I remember would manually bomb in the stages and his chain didn't cut. I'll have to check on this again.
On the difficulty:
I'd say this is a very hard game indeed. Even with Shot types it's very difficult to get past stage 3. If they keep this difficulty in the final product I will be amazed. They billed the game as easy for beginners to get into, but that couldn't be further from the truth right now. Guys were getting reamed left and right by the end of stage 3, and these were no shmup schmucks. I saw one guy nearly clear DFK BL with Strong style right before his SDOJ credit and he still got mauled. Another guy was destroying Ketsui for awhile, and his credit ended at SDOJ's second boss with Laser Style. I couldn't see much difference between Shot and Laser - perhaps they are the same in regard to bullet patterns?
On the bullet patterns:
They remind me a lot of stuff in DOJ, and Ikeda's recent arrange modes DFK Arrange A and DFK BL Arrange. There's also a lot less slowdown than other SH3 games, the bullet speed on the bosses felt like Futari 1.0 (not 1.5) Original but with more density.
On the graphics/music:
Both are fantastic, top notch stuff. Lots of voice work in the game too.
There was no feedback card to fill out so it seems like Cave wasn't interested in what we thought about it. Oh well.
Anyway I'll probably head down there tomorrow morning and try and take some pictures, I didn't have a camera with me today.