I have issues with Terrier 2s. Loads of them have the star shaped thingy such that you can't get the number viewing port to line up where you want it to, the numbers fade in the sun, and they allow a small amount of flow even when the room temperature is 12° and they are supposedly set to 'frost' (8°IIRC). Also the temperature range between fully open and fully closed is far too wide for my liking.
Are the Terrier 3s a big improvement?
Danfoss RAS C2 do seem to be better quality and design (even if they are a bit ugly to be honest) even from the close control of temperature point of view.
Actually, I find it weird that when the horizontal position is the preferred one from a technical perspective, nearly all TRVs seem to be designed to look best installed vertically.
What do people think of the Drayton TRV4? Never installed one, but they certainly look good.