The wave of new London bike shops

What's it supposed to mean? Exactly what it says. Nowhere did I say that "all mass produced far east frames are rubbish", because that's demonstrably bollocks.

If, like me, you're in the trade, you'll know that Ridgeback bikes have a rep. Not for nothing are they known as Ridgecracks. They're cheap yes, that's not unique, but there's cheap and very cheap. A lot of RB frames are now made not in China but Laos, Vietnam and Indonesia. Quality is patchy at best; welding cheap steel and alu still needs care, and I've seen a lot of failures around the BB areas where excessive heat through bad welding has weakened the tubing. This isn't unique to RB of course, but they're the worst of the brand named bikes, imho. It's got to the point now that if I get a bike bought to me for a service the first thing we do before we do any work is clean the frame and check for cracks. I'm glad you're having a ball with your Solo, it's not a bad bike. It's their lower end stuff that's not so good.
Genesis frames are just odd. They should be good, they claim to be using Reynolds 530 etc, but fuck knows what they do with them. They just shouldn't be that heavy and unresponsive. Maybe it's bar, not tubing?

As for options, for steel I really like Surly frames. Decent quality steel, well specced in terms of braze-ons and reasonably priced. They're frame only of course, so you can do a custom build on one. Brother are nice too. Alu? Go for a good brand - you can't go wrong with Trek or SBC, with their lifetime warranties. Carbon? Caveat emptor. Go for the best you can afford. Avoid cheap shit like Planet X like the plague - cut one open and you'll see why. There's a reason they're cheap and light. I wouldn't put their forks on a wheelbarrow, let alone a bike.

Will stop now, I'm rambling.