Not so good, spindle bearings are not the cheapest of things although these shouldn't be too bad in comparison to others.
Think I got mine for about £70 but that was a few years back.
Beaver NC5 ones I think were around about £150 but took quite a bit of emailing to find them at that price.
Chiron ones were over £200 and that was dirt cheap, I just happened to come across a place in Switzerland that had them as excess stock, filling in all the forms though to get them was a real PITA but still saved at least a few hundred.
Yes, have used them as well, good prices on standard bearings, that is where I got the ones for the Chirons tool holder, half the price of other places.