SGLP and SGLN are probably your best options, they’re cheap (0.12%) and the biggest/most liquid. XGDP is marginally cheaper at 0.11% but not as liquid and denominated in dollars so you’d pay a 0.15% forex fee on top.
It’s been decades since I looked at physical gold. But I always liked Krugerrands, which tended to have the lowest premium of the Troy ounce coins from different countries. Sovereigns could be an option but the varying, arbitrary seeming weights always put me off. Ideally, you’d want to try to collect some coins of value themselves – ie as well as the gold, low number in circulation etc. But getting a bargain on say a 1933 US double eagle is far, far easier said than done!
I hope that’s helpful. As to the choice between the two, I was a right gold bug for a time but I’d just buy an ETF nowadays though I don’t actually hold either.
have a look at Royal Mint Responsibly Sourced Physical Gold ETC - RMAP. holds recycled and responsibly sourced gold exclusively. held by the Royal Mint in their vault in the Welsh countryside and one of the most secure in the World. also you can redeem to demand for coins and bars. You can get USD, Euro & GBP hedged as well. For disclosure I work for HANetf who distributes RMAP. AUM is around $1.4bn so decent size as well