If you want to trade FX but want to see the Bid/Ask, the workaround I use is to chart the Futures contracts. Cos it's centralised with the CME; you will get the correct volume data, not broker-specific data. EUR/USD is the 6E contract on the CME.
That's the only workaround I can think of because if you want that accurate Bid/Ask, you will need the tick data.