Press Fit Bottom Brackets

Frankly, I think they're completely shit!
To put it mildly, I F?$&@ng hate the things.
I'm on my third now and apart from the Husky and the Scott, I never take my bike out in the mud.
I have BB30 on my other bike and love the way you can buy bearings from a bearing shop and swap/service them yourself.
The bearings on a pressfit are glued in so you can only remove the seal from one side to service it. Once it's gone, you have to fork out for the whole unit.
The bearings SRAM use are obviously cheap but I heard a rumor that Chris King were bringing out a quality unit soon.
Someone should make a sleeve that fits in your frame that enables you to take just the bearings out to replace them instead of the whole unit.

G'day, have changed a couple - they are not glued in !!!

However they can't be taken out generally, cleaned then refitted - they are a disposable non serviceable part . My experience is with the bb91 and have failed in mud but the other has done 2000kmin all weather

Biggest adv of threaded is they are 25 from crc whereas bb91 is 50$. Getting replacement bearings is only useful because they can be found quickly. Of I could choose a frame I d choose threaded - not least of all because you get a free bb with a crankset. But press fits just mean when it's farked - you replace it which is a 10 minute job

New carbon frames come with massively oversized BB shells and don't have alloy inserts to take bb30 or screw in bb's so they now have a bearing with an outer plastic casing that is pressed into the carbon frame.
The bearings outer races are bonded to the plastic shell so when they fail, you have to buy a whole new unit.
It's just another way for the bloody manufacturers to hold a monopoly on parts. You can't just go out and buy your aftermarket bearings anymore.
Someone needs to design a pressfit adapter that returns your bike to a bb30 style where you can change/service your own bearings.
Slowpup! Here's a challenge for your engineering genius???

You're right gazza, you can't get the fekkarz out just as bearings - but taking the whole plastic thingy out is pretty easy - as long as you realize you are going to stuff them by removing them. Everyone seems to be pretty down on the things , but I was very surprised at how easy they were to change out and of course you don't need a bb tool to remove them either .

As to longevity - I don't replace them when they start making noises because invariably they become quiet after another 50km. When they start being hard to turn the crank aND noisy - then its a replace . The SRAM press fit s are sort of serviceable - you can pick the bearing cover off without removing them and pump some clean grease into them

I do keep a spare routinely- bought at the appropriate price of course !