I own four bass combos, including a Bassman 150. It's ok, but compared to the MB112:
- it's substantially larger, and more awkward to carry due to it's size and shape;
- the speaker isn't as good;
- it doesn't get quite as loud, and the bottom end is weaker.
Since getting the MB112, I think the Bassman 150 has been out on a gig once. Will sell it eventually. The GK is an easier carry, and has more grunt. There are features I like about the 150, all on the preamp side. The kickback feature can be useful, but is also a major contributor to the awkward carry. The power stage isn't class D, like the MB112 and most of the amps recommended here. I'd prefer it in a smaller cab with a better 10" speaker than the cheap 12 it comes with.
I'm certain you are right in all of your points. But, hey, it's $99 so a total investment of under $140 with a 45-day return policy. So it's not a gamble.