KiwiSaver provider Simplicity say the devil's in the detail of a Kiwibank investment opportunity

The Commerce Commission's found the sector lacks competition - and is dominated by the big four Australian players.

The Government says it'll look for up to 500-million-dollars - from parties interesting in putting money into Kiwibank, to drive competition.

Co-founder Sam Stubbs says banks are typically a good investment.

He says it depends on how much they're raising, what the price is and whether or not you can sell your stake.

Stubbs says in principle, it should be a pretty attractive investment.