Well done! I like the 3po better, the R2s weathering is very uniform in that the dirt looks too random, i.e. not created by various "events" or over time but simply "splashed on". You IMO could improve on that by i.e. using a thinner to create runny lines and deepen the cracks by have the paints pool up. But in the end it all comes down to personal preferences.
Btw, the threads title could be a tad bit more informative, i.e. contain information about the project like "Bandai (?) R2 and 3PO kits build and paint job- almost done", tho helps in attracting interested members and navigating through the forum.