I am thinking exactly the same. I saw an interview a while back with Paulie Malignaggi and he said something like "I've seen Spence Jr hit and he hasn't reacted well to it". Now, if true then I believe that is a worry for Spence Jr and his backers because as you have said he hasn't fought anybody with that much power and Brook can dig at 147.
I remember watching Clinton Woods smash Rico Hoye years ago and there was a feeling that the Americans only sent the prospects they weren't sure of over here. That seems to have gone away a bit with the likes of Tim Bradley coming over and doing Junior Witter and Tank the other night but it always sticks in my mind. Spence looks such a clean and accurate puncher but other than stuff Bundu and limited Algeri he hasn't fought anyone he shouldn't look good against. The finish against Bundu is chilling stuff but just have a sneaking suspicion that Brook is gunna get to him, a few people now mention he's been hurt more than once against non punchers - Brooks one of those guys he doesn't have a fearful KO record but just about everyone in the games says he can crack maybe the americans have overlooked this.
You just put the tenner on brook at 6/4.there is a catch as I thought there might be.if he wins they pay you out at 6/4 and then pay the rest of the 9/1 by way of a betting token of 65 quI'd. You then have to place that 65 quid bet within a week of it being accredited to your account.any winnings you get from that are then yours.still worth doing