I reckon these "free" US brokerage accounts probably get you on the fx rates

Yep. This too. I've been using it to buy small parcels in a mini etf thing. With the paperwork and now change to the brokerage I wouldn't recommend!

I’ve got way too many brokerage accounts (don’t get me going) for different purposes.

CMC - offers free trades under $1000 AUD per ticker per day for ASX stocks. Great for Dollar cost averaging and the small cap portfolio. It also offers free US trading and also allows trading of some European stocks (but brokerage fees are high). The forex happens at the time of transaction and cash is held in an interest bearing Macquarie Bank account (that you can see from within Macquarie internet banking). Downside of their international trade is orders are day only (I think with extended hours trading)

SelfWealth - offers fixed price $9.95 trades on ASX, US markets and HKG (similar numbers when translated to HKD). Good if you’ve got a large chunk of money to invest. However, their cash handling is pretty shit (some sort of custody account that’s really hard to get statements from and you need to transfer your AUD to either a HKG or USD account before you make trades). Nice thing about their international trading is you can do limit trades that last for I think about a month.

CommSec - this one is a legacy for me and definitely not discount brokerage (but I do find some of their research and tools pretty good)

Interactive Brokers - my newest toy. Got this account specifically for Covered Call Options trading (the brokerage on options contracts are dirt cheap). It also has the advantage of being able to trade on lots of international markets if you want it. Downsides are also many: really complicated interface (intimidating), not chess sponsored (although custodian model is pretty much what all US shares are). The biggest frustration so far has been getting my different entities setup … individual account done but more than a month of wrestling with SMSF and Trust for the options trading permission and still not solved (I think its some specific setting during the applications process, but its super frustrating as its the same monkey on the keyboard making all the trades anyway and for each of them, its only a small proportion of my portfolio I’m going to engage this strategy on).

I'll put a vote in for CMC.

I opened an account for my recently turned 18 year old son and the free trades under $1000 per day is perfect for the relatively small amounts he is putting into the market.

Set up was completely online and took about 1-2 days for the account to become functional.

CMC does charge a 0.6% FX fee on US share buy and sells. I've got a spreadsheet & linked word document where I put the buy/sell details in to calculate the costs and manually amend the details in Shareshight as brokerage (accountant was happy with this). I've been in touch with Sharesight to see if they could integrate this automatically (all the details are in the Trade Confirmation) but they put it in the too hard basket.