Depends what you want from your 3rd party Dinobots.

You've got combining ones by Toyworld and GCreations.

If your after CHUG sized Dinobots, Fansproject are doing really nice classicsverse ones and Planet X have their Fall of Cybertron ones.

The MP sized Dinobots have Fans Toys and Gigapower. Fans Toys have a fair bit of die-cast in them and feel really sturdy. Gigapower on the other hand are giving us the biggest dinobots.
There are other companies like Bullsfire doing MP sized dinobots but they're coming out slowly and I'm not sure they'll grab enough of the market to complete their lines.

I'm collecting the Planet X dinobots. I just like their aesthetic.