Having cleaned the bike earlier I’ve found that there is some play in the bottom bracket (Deore crankset) so am assuming it’s new BB time.

Is there a significant difference in quality between the Deore Bottom Bracket and the SLX / XT Bottom Bracket (BB70) ?

Also am I supposed to be performing regular maintenance on the BB to extend it’s life?

I have considered a Hope BB but have no experience of how long they last and whether they are worth four times the price of the Shimano BB?

I found a big difference between deore and SLX BBs… In everyday use I reckon SLX last about twice as long, maybe a little less. (otoh I destroyed a deore one in a single day on the dh bike! Obvious wrong part for the job is obvious)

Hope is better… But you can get about 4-5 SLXs for the price of a Hope, and Hope isn’t 4 times better. Depends how you feel about disposable parts though. Shimano are essentially unservicable, you can remove the plastic cap and clean/grease the bearings but it’s a hassle and you’re relatively likely to damage the cap. Oh, also Shimano are pretty sensitive to overtightening, whereas Hope aren’t.

Another good alternative is the Gusset EXT24- lasts a little longer than XT and is slightly more servicable, the bearings are easily accessed if you want to clean them. But also, very easy to replace the bearings in, unlike Shimano where it’s (I think intentionally) slightly fiddly. Comes in pretty colours and costs not too much.

Having said all this, Shimano tend to die from seizing up rather than going slack so I’d check it all first to make sure it’s not just loose 😉

I’ve just replaced my shimano Deore BB after less than 6 months, as far as I know they are unserviceable as it even says don not disassemble on the bearing cups
I took the plunge and went for a hope one with the ceramic bearings, fully serviceable will all parts available as spares, should last years and will work out cheaper (and less faff) than changing every 6 months

Hope is better… But you can get about 4-5 SLXs for the price of a Hope, and Hope isn’t 4 times better.

IME about 6 times better, based upon how long my first two HT2 Shimano’s lasted vs my Hope.