Hi Skysearcher, I've had my 12" Bintel premium Dob for 2 years now and love it
. I'm no expert, but optically I think it is very good and I'm sure a lot of others in IIS land would agree with me. I get stunning views of deep sky objects such as M42, Carina Neb, Tuc 47, Omega Cent., tarantula etc etc etc. But I also have great views of Saturn & Jupiter. Well collimated, I get nice sharp star images and great lunar detail.You can get great views of planets with a dob! Of course, it helps if you have good EP's as well. I've only got 2 EP's- a 24mm Panoptic & a 8.8 Meade UW + a barlow and I'm as happy as a pig in %@#*!
I would highly reccommend this scope to anyone.
Hope this helps
Simon