Yes Shanghaiceltic, our Collins class subs are real lemons. I think the Swedes should give sub design a miss and stick with frilly underwear.
Most of the 6 subs have been in commission from 2 to 6 years and its doubtful if they're operational. They are continually docked for re-work.
The first combat system installed didn't function. That had to be thrown away and a new one from the USA installed. That was a couple of extra $billion on top of the $5 billion and 12 years to construct them. The sonar was only 25% effective, the periscopes and propellers were faulty and the hull was too noisy. An American team was called in to investigate the noise problems. When interviewed, the team leader said it was like listening to an underwater rock concert!!! It might be a new weapon, you generate so much noise that it blows the crap out of the super sensitive surface listening instruments.
Okay, they all had to have their hulls re-shaped, another $266 million each. Then they had to be taken out of service with dodgy underwater valves. All up, the additional mods come to around $5.5 billion.
And now the navy is having trouble finding crews for them, only 45 per sub. No wonder, the sailors, and their families, are starting to feel very chary about these boats. I was a sailor and my son is a serving sailor. I told him not to bother volunteering for submarine service as I would choke him first, at least that way I get something to bury.

JG/FME.