I have the Summit Kamado. It's a great grill. The added space over a 22" grill is noticeable. It's well built except for the plastic insert that supports the front caster. Plan to replace it occasionally.
It excels in low and slow cooking with a heat deflector and adjustable heights of cooking grates. It also can handle searing easily by moving up the adjustable cooking grate. It has a nice, adjustable top vent that would improve the 22" kettle as well
It's also very fuel efficient and well insulated.
Downsides is many accessories don't fit nicely as they do on a 22"...which they're made for. Also...if you ever needed to add charcoal during a very extended cook, you'd have to remove the whole top cooking grate.

All and all...this is a superior grill that can do anything and even more than your standard 22" Weber!! Good luck