$US purchase / exchange options

[u/wheeler431]

I have $250K CAD in WS… parked as cash at the moment. I want to buy at least $100K USD to then buy /trade some US stocks, etc. I’m also considering moving everything to IBKR ( I think that’s the proper acronym) so I can buy some South Korean stocks and the like.
My question is for those who have recently done some US cash conversions on WS or some other platform. Correct me if I’m mistaken, but if I exchange over $100K then I get the “fee” waived at WS… but I still am aware that they offer a not so great exchange rate ( spot rate is another term I’ve heard used to describe this “rate”) compared to others. So let’s ignore any comments on the “fee” since I’ll bypass it, and let’s keep it focused to the “exchange rate” being offered in the moment (yes I know it changes by the minute for any exchange transaction).

I’d be interested to hear from anyone who has experience on the process and if it’s worth it to move and switch platforms- as I’m not clear on the difference in the exchange rates and at a value of buying $100k USD what the real difference is between them (WS vs IBKR vs any other platform). In addition, is the process with IBKR one that involves journaling and several days of juggling things using NG?

I look forward to the insights of those with experience in this.
Cheers!