I have a mini rex now and unlike velvet fabric and regular fur it feels soft even if you pet bunny from tail to head, not just head to tail.
My current mini rex is pure bred and her head is small compared to her body. She is overweight at 1.9kg.
Years ago I had Black velvet. She had very soft fur too, yet perhaps a bit longer than Heidi's. She was likely a mix. She was 2.5kg.
As Jane always says rexes are hungry bunnies.
I had to read you post twice because I thought autocorrect changed Boo to Bob in regards to nugget sniffing.
New bunnies usually smell different until they are here several days. I wonder why?
I hope Boo will like him as much as us humans.