I have now 10 different DE blades to try. I wondered what people's methodology has been in deciding which blades work best for them. I currently (only) have an EJ DE89.
Take everyone's opinions with a grain of salt. What works for one person won't work for another.
That being said, there's some general things that work for most. For example, as your technique improves so will your shave. That means, a blade you test and write off when you're just starting out, may one day become a favourite blade once your technique has improved. There's also some blades that tend to not work for most people and so generally ought to be avoided when starting out.
I am simply choosing a blade, shaving until I think it is worn enough (starts to pull), then choosing a different brand to try. Rinse and repeat.....
Any better way?
Yes. I would try three different blades and then choose your favourite. Stick with that single brand of blades for a couple of weeks. Then you'll have a yardstick by which you can measure other blades.
After you're regularly comfortable with a single brand of blade as you've used it for a few weeks, then choose another brand and use that for a few shaves. Assess it against your "yardstick" brand as either "better" or "worse".
If it's a keeper, then use it a couple of weeks so it becomes your new yardstick... This way you have something to compare against. There's no point just whirling through the blades too quickly without being able to compare them against a standard. You need to create a standard for yourself.
Most of the blokes here, I say, would have a brand or two that are their "yardstick" blade in which they compare all new blades against.
Do you end up having a favourite that works across more than one razor or can one blade be great in one razor and be crap in another?
Yes and no.
Yes, you will probably end up with a favourite blade.
But no, it won't work across all razors equally well.
I'm with
@Mark1966 on this when he says that different blades work in different razors. It could be a mild (comfortable and low efficiency) razor with a very sharp blade combo. Or simply that one particular blade works far better in a particular razor than any other.
(Although
@Mark1966 has a much clearer way of stating this point...)