RetireJapan

So since all iDeco providers are restricted to max 30 fund I believe SBI lost its current advantage it had over the other providers.

I am really interested in only one fund . All world/developed countries index.

Currently I have been buying SBI DC Nissay 0.3% trust fee
would in make sense paying the ¥4000 fee and switching to Monex and buying iMaxis slim Developed countries trust fee 0.19%?

You can probably run the numbers and see how much difference the fees make to the amount you will invest over the timeframe you can invest it.

I'm in the process of switching my wife's account from Iwate Bank (used to be one of the best, but no longer competitive) to Monex. The paperwork was pretty easy, but it has taken several months and the process is still not finished so there is going to be a 'time out of the market' penalty too. Currently my wife's funds are all in cash waiting to be transferred it seems.