I found the Dark Angels models to be great fun to paint - the latest generation snap kits are really something - and the Tactical Squad especially are a very nice addition to an army. The only down side is they are covered in detail and DA insignia; I wouldn't recommend buying these with the intention of removing the badges for use in another Marine army.
I chose to paint these models in the GW style, using their painting guide from How to Paint Dark Vengeance (on iPad). The only real change was to mute the choice of greens a little; the very sharp green highlights do look nice on the tabletop, but were a bit too stark for my tastes.
