>>1214995/diy/ here,
You can get a length of steel wiring conduit, cut an about 12 inch long piece, then cross-cut the end for about an inch or two, flare it out a bit, and voila, you have a home-made tool for removing Pressfit BB's, and it only cost you a few bucks.
If you're really cheap you can also just use a drift pin and a hammer to tap the old bearings out, but they'll likely come out in pieces.
Next you get a very large bolt, long enough to reach all the way through with plenty to spare (and threaded it's entire length; important detail), a few flat washers to fit, and of course a nut. Put one washer on the head end of the bolt, get one side of the new bearings started in the BB, put the bolt through, put enough washers on the other end to shim it up so there's enough threads to work with, put the nut on, then hand-tighten it. Make sure the new bearing is straight and the whole rig is straight and square. Now with a wrench on both sides (or a wrench on one and a ratchet and socket on the other) start tightening it, pulling the new bearing in, making sure everything stays straight. Once all the way in remove the bolt, insert the spacer, get the other side bearing started, and repeat the process to get it pressed into place. Done! Install your crankset and you're ready to go.
See? No special tools required to *buy* if you don't want to, you just have to be clever and creative. Of course you can buy them if you want; I recommend buying the removal tool and using a bolt/washers/nut as above to install the new one, you save a bunch that way.
Pain in the ass? Slightly. But the fact of the matter is: even a threaded BB requires a special spanner, and you really need the socket type (that can be put in a ratchet or torque wrench) to do a proper job, and that's not cheap either.
The main advantage of threaded is you can remove and reinstall/reuse them, you effectively can't with Pressfit, which annoys me.
