Wait for inheritance or bring forward?

For context we are 33 earning a combined household income of around 300k with a 1 year old. We have an investment property with 1m debt and about 400k in equity and were recently asked by our parents if we'd like to take over their 1m mortgage on their investment property (valued at 3+) and move in as they intend to hand this down to us in their will (originally did this way to avoid cgt and stamp duty).

On reflection we are now paying down 8k a month on a property we have no accessible equity on so we wouldn't benefit for another 20 years assuming we just make minimum repayments and this is very much impacting our ability to invest separately. Is it worth wearing the stamp duty and cgt (approx 600k plus a 1.1m loan) to transfer the property (and officially take over the loan) and then use the equity to help us invest further and boost our ability to retire early?