GLBenchmark is the best program for GPU testing. Very intense and thorough. Here are results by GPU:
GLBenchmark GPU Results
Notice where GC860 is? GC1000 would be *slightly* better than that. Click the links to see that actual tablet list and ranking within those GPU results.
PS, Benchmarks are better for gauging performance instead of specs. ie. some company may give the best specs but performance testing reveals the truth. =)