SPP Harvester by OnMarket, page-730

And the much lower selling costs, mngt fees & performance fees!

For me so long as the IG service is on a par with IB it's a better option.

We've clearly seen on low volume shares IB is at a clear disadvantage to a single seller via IG.
The option to not participate is obviously also a good plus & to put more money into more favourable SPP where there multiple SPPs.

Unless a SPP is only marginally below the issue price my intention is not to hold past the first opportunity to sell.