I do mostly interiors, I've tried (have) buckets full of brushes and my favorite to date is the Corona Shelby 2 1/2" angle with a beaver tail handle, it's Tynex Nylon and I've been using them with different brands of paint and it's just the best thing I've ever worked with, I have plenty Purdy and Wooster brushes, both nylon and mix bristle but the Corona (it's also called Champagne) I got three of them to try out and it'll be interesting how they work in summer.
I'm in the NW and find quite often I have to change brushes from one day to the next with the same paint, depending upon the heat (or lack of) and humidity (rain outside for days or weeks), often starting out with one brush and switching to another bristle after lunch. Not often but enough to notice.
I've otherwise used the Purdy 2 1/2" Blue Jay Beaver Tail angle (has the copper ferrule and is made of nylon and poly) that's the one I used most until recently. It's the same shape as the Corona Shelby but doesn't seem to have as many bristles (cuts pretty well but doesn't load up nearly as well as the Corona), also the quality control regarding the chiseling over the last year has really gotten poor. I'll go through a dozen at the paint store, searching to buy two.
I ordered three of the Corona's over the internet and took my chances and they're all perfect, the best cutting brush I've ever used in the 7 years I've been doing this. This week I had to remind myself that I didn't have to be super extra cautious to prevent brush streaks, today I had to use a pole up about 9 feet above me with the brush in a holder over my head and cut an edge in a place I just didn't want to put a ladder, nice line, oh yeah I was real careful, took my time but did it, I can't remember being able to pull it off quite to that extent and that well with other brushes in the past and I do take pride in being able to do that sort of thing when I absolutely, positively have to.
Sometimes I use the Wooster Ultra Pro Soft 2 1/2", it's a nice brush too, just a hint stiffer than a Purdy Nylox.
But the Corona Shelby Corona Tynex Nylon gives me the best loading, smooth finish for water based paints, flat and eggshell easy but especially semi-gloss which some brands don't cover as wel, the Corona just works better.
Roller covers, Wooster all the way, 50/50 when I can find them, but mostly Super Fab, even with semi-gloss on heavy knock down texture, 3/4" cover, used to use 1/2" for years but the Super Fab works better with the thicker pile, I do have two apartment buildings where I prefer the 1/2".
I also use the Jumbo Koter 6 1/2" Wooster rollers almost exclusively doing bathrooms and kitchens, some Super Fab but the Pro Doz 1/2" mostly.
I love that weird Wooster Polar Bear for heavy knockdown when I can find it but that's almost never around here.
