Which is a better option and why? IWDA or SWRD?

Both tracks the same MSCI World Index, both traded on LSE, both accumulating.

Differences are:

TER: IWDA 0.2% vs SWRD 0.12%, SWRD cheaper.

Vol: IWDA much higher volume than SWRD, IWDA has better liquidity.

If you are long term investor, TER would be more important factor because it will affect the long term performance. Liquidity is important for shorter term trading.

In the long run, I don't think it will matter. The reason why SWRD's volume is rather low is because it is relatively new compared to IWDA. SWRD is also run by SSGA, which is one of the Big 3 ETF issuers.

Volumes should increase as more people and institutions discover that SWRD has a significantly lower expense ratio of 0.12% vs IWDA's 0.20%.​​​