Interactive Investor Hidden Costs

So I'm just trying out a few trading platforms. Can't be bothered to read all the small print, the key thing is deciding whether the provider is seeking to deliver a service to you or just profit from you. If they are going to screw you you obviously go somewhere else.

So I made a trade which is listed in the history thus:

No Shares: + 8
Price: 123.76
Consideration: US$990.08
Commission: £8.00
-----------------------
-£813.74

And sold the following day

No Shares: - 8
Price: 129.09
Consideration: US$1,032.72
Commission: £8.00
-----------------------
£818.00

Leaving the account with +£4.26 (T)

But the actual difference in consideration before declared commission was +US$42.64 (P)

and Total Commission: +£16.00 (C)

So
$P - £C = £T

$P = £T + £C

US$42.64 = £21.26

So IG is expecting me to accept an exchange rate of £1 = $2 which is ridiculous.

The actual value over the last few days has been within the range 1.23 and 1.25. Let assume the strongest pound of £1 = $1.25.

I should have seen £34.11 not £21.26

Which means £12.85 has gone missing somewhere not made obvious to the user.

That appears to show clear and deliberate intention to defraud the customer. Perhaps it's buried in the small print, but such behaviour is obviously designed to mislead.

Conclusion: do not trust IG Index.

Trying Interactive Investor now.