I can't comment on the Butlers items, other than in reference to the photos I've seen posted on them, of which many appear to be quite grainy to me.
They do offer their products in various scales, and when they post the photos, it is unclear to me as to which scale(s) they are showing, so perhaps in 1/144th the graining is less prevalent, if the ones they are showing pics of are in larger scales.
I have purchased some of the Kamiya minis in 1/144th scale, and I must say they are superb. They rate right up there with the Shapeways models, and may in some/many cases be superior to them. To be fair to SW, I usually only purchase the less expensive, white plastic minis, since I find their "fine" products to be cost-prohibitive in most cases.
The Kamiya models are very nicely printed, and only on a few minis and angles of the surfaces of them shown any layering at all, even on armor with complex curves and sloped armor.
I can personally recommend the Kamiya models, and must say that I really like them.
Another supplier in this scale, for rare and very nicely printed minis is Panzer-Shop.nl
They are worth checking into also, and they produce WWII, Cold War, and Ultra-Modern vehicles in 1/160th scale, but you can get them to provide minis in 1/144th scale too, for slightly more.
Both Kamiya and Panzer-Shop occasionally offer some stuff on sale, which helps a bit, since they are not inexpensive.
If you are interested in metal minis, and can deal with slightly smaller scale, Red3 is a new company churning out a lot of really nice sculpts in metal. Their minis are 1/150th scale, so about 4% smaller than the 1/144th scale minis, which means they're about 1mm – 2mms smaller than their larger cousins. I don't have any of these yet, but from the photos I've seen on-line, they look to be very nice, so I hope to acquire some of their items too, as the Defense Budget permits.
I wish they made stuff in 1/144th scale, but I guess I can deal with the slight size difference for some models I don't already own.
Arrowhead also produces a very nice range of minis in metal, in 1/144th scale, and they are less expensive than the printed plastic minis, so are worth a look too. Quality of their sculpts is superb also.
Most of Arrow Head's product line is for WWII, but they offer a few Ultra-Modern vehicles as well.