Need one, never used one.
Apart from the El Cheapo Ebay ones, there seems to be three price breaks;
£30ish £50ish and £100 plus.

You should avoid all three price points.

They'll all be crap, I'd get the cheap one!

I've used a RaceFace signature XS ISIS bottom bracket since the concept first arrived in this country (I was working in the trade at the time). This bottom bracket is still going strong. I've had the bearings changed once at a cost of £30. I'm more than happy with that.

If you want to spend less, have a look at the SKF ones or dare I say, superstar components. I've not tried one of theirs but they use itegrated bearing races which allows for bigger balls so should over come the ISIS short coming.

>I've used a RaceFace signature XS ISIS bottom bracket since the concept first arrived in this country<

Err, that's like 8 years then?

Seriously, unless you are a very light / low mileage rider one replacement in that period is unheard of ime. I've used the RF XS FR for 7 years and have had to replace bearings on average every 6- 9 months. I've tried other ISIS BB and they are also crap – sinilar life expectancy to the RF offering. Wouldn't mind so much but the bearings are overpriced and I've never been able to find OEM versions of them at less cost. The grease port idea is also irrelevant as the small bearings disintegrate long before re greasing becomes an issue.

Currently running a Superstar BB which has also died after 8 months thus failing to justify the move to a completely different BB.

Have heard that SKF lasts but no change out of £50 iirc so not worth the risk

Avoid the system – it's sh1t

They're all rubbish. There's only room in a BB shell for the big ISIS axle and teeny tiny bearings. They have no strength. How small are they? This small .

The crank brothers ones have a good guarantee.

Cheers, al.

Yep, 8 years sounds about right. In fact, my bottom bracket was so early that it didn't havew the double width bearings fitted but used two deep groove sets either side. When the bearings were replaced about 2 years ago, they fitted he double width type with the grease hole. I filled them full of Silkolene RG2 before fitting and I've done than about once a year since. I ride all year round in the peaks so I don't think I'm a particularly light user. Maybe I just got lucky!

Some of the cheap VP ones don't have the outer sleave peaned over the cartridge bearings, so with a bit of fiddling you can knock the old units out and replace them.

I'd say go cheap or go crank brothers at about £60 that gets you a 5 year warrenty.