Have not used those specific models, but am quite familiar with that exact 10" alnico/pepperpot driver (same used in Kensington GR) versus the tulip 10". The alnico simply renders a more vibrant, brilliant sound - especially in midrange. More immersive and visceral. The tulip might actually be a little smoother and better extended up top, but alnico's midrange wins it overall. The tulips do sound very good, though.You won't notice you're missing anything, until after hearing the alnico drivers.
Back in the UK days, these driver replacement parts cost an order of magnitude more for alnico - like $3K each, versus $300 tulip lol. The alnico material isn't cheap, and they use a lot of it. So that's the price difference.
I also have the China-made 10" alnico and it's very, very good - so no worries about that. The 3rd party crossovers from MainlyTannoy (UK) do sound much better than Tannoy's, if you're willing to do that.