I like the BSB Swiss bearing because they are grease packed. You need to put on 50 or 100 miles before you do a race with them but they last much longer than an oiled bearing. As you skate the grease gets spun up against the shield where the inner race meets the shield and creates a barrier between the contaminants trying to get in and the balls and race.
Here is a picture of a brand new never spun BSB Swiss bearing with the nylon retainer removed. You can see at the factory they just put a dab of grease on each one of the points in-between the balls. Then when the retainer is inserted into the bearing the grease gets put (spun) directly up against the shield where if dirt was going to get into the bearing this is where it would get in.
This makes it very easy to re-grease a bearing as you put only a dab of wax based low temperature grease (not petroleum based high temperature grease) on each one of thse points. I have seen some people over fill a bearing with grease and then wonder why it won't break in.
When I put a brand new set of oiled Bones Swiss in, within 5 minutes I can hear dirt grinding in the bearing. With the BSB I can go 8 months or a year before I hear a speck of dirt in the bearing. With both the BSB and Bones the balls and race come polished with a mirror finish. Scratching the mirror finish will cause resistance. Within 5 minutes that mirror finish is gone with the Bones but with the BSB it will last a year if you don't go through water and push the grease and dirt into the race.
With the BSB you don't have to clean them, you just move the bearing to your new wheels being careful not to get dirt in the bearing from the inside (there is no shield on the inside). The BSB are packed with the perfect amount of low temperature wax based grease as opposed to a high temperature petroleum based grease. Low temperature wax based grease will liquefy at low temperature. This is good in that if and when a race becomes dry (free of lubrication) and friction starts (which creates heat) the surrounding grease will melt and relubricate the balls and race.
This works well in that only the dry race will be lubricated one at a time as they get dry without you having to do anything. This leaves the race and balls with the least amount of lubrication possible before relubrication which ensures the least amount of resistance.
20 freshly oiled bearings will create more resistance than a broken in set of greased bearings that has only 1 newly greased bearing from the heat of a race that dried up and heated some grease into the race. After a year just throw your BSB's away and get a new set for $100 or clean and re-grease them and use them for your rain bearings.
Bones bearings are good if you have no BSB broken in and you have a race next week. Out of the box the Bones are a little looser than the BSB (no need to break them in) and being oiled they are race ready right out of the box (but your mirror finish would be gone 5 minutes into the race). Bones are also good indoors where there is no dirt to get into the bearing. Outdoors Bones bearings just seem to be a dirt magnet.
If you want a bearing that will be like new after a year then get the BSB Swiss but remember the first time you go through water whether it's the first day or the 300th day the mirror finish is gone.