I've selected a few companies whose kits are clearly produced to cater to the collector/modeler who likes to build and display accurate kits. The casting quality is very good, there are lots of nice parts, and the detail is accurate. The kits are too nice and possibly too fragile for frequent handling.
Here is a list of companies whose models I have purchased. I do not plan to include lists of models made by specific companies, as the availability of what is currently being produced really changes much too frequently.
AZIMUT/ADV. French modern vehicles. Very good quality resin kits from this French company. Very complete instructions.
EXTRATECH: 1/72 resin & photoetched kits. Very nice casting quality. Instructions and decals. Available at Mighty Military Miniatures (see above).
FINE SCALE FACTORY: (Bellerslohstrasse 19, 58452 Witten, Germany). 1/72 scale kits, mostly WWI or earlier subjects. The casting is very nice with distinct details and no flaws.
MARS from Poland. Extremely nice casting with a lot of parts.
MODELKRAK from Krakow. Kits have a mixture of resin and metal. Occasional detail loss, but very nice series of kits. Carried by Jadar-Models (see links).
MILICAST MODELS from Scotland. 1/76 kits. Models have many parts, some small. Good to superb quality. US distributors are Squadron, APC Hobbies, and Hobbyweb (see their websites or consult your hobby store). MILICAST, P.O. Box 711, Glasgow G41 2DS.
RESIN MASTERS. Sculpted by Peter Bunderla and available through Ostmodels. The quality is very nice, and there is an interesting selection of 1/72 and 1/76 scale kits.
MMS MODELS. White metal kits in 1/76 scale. Distributed in the US by Brookhurst Hobbies, 12188 Brookhurst St. Garden Grove, CA 92640. WWII vehicles and figures. Carry some interesting items, such as the british Tetrarch light tank. The quality is very good. MMS Models, 26 Crescent Rise, Luton, Beds., LU2 0AU - U.K.