Tenby Internation school at Tropicana Aman-  10-acre international school campus-a built-up area of about 225,000 sq ft that could accommodate up to 1,800 students.
Tenby International School at Tropicana Aman is expected to have its first intake in September 2018, offering international student-oriented programmes for students age three to 18 years old, including international primary curriculum, national curriculum for England, International General Certificate of Secondary Education (IGCSE) and A-Level programmes.

http://www.thestar.com.my/business/busines...-school-campus/
Oasis International school at Bandar Rimbayu - Phase I of the building construction with a capacity of nearly 600 students; when completed, the facility will house around 1200 students.
Oasis is expected to have its first intake Q4 2017 or early 2018.
Mr. Ben Hale, Director, states: “We will offer an innovative academic model which offers a wide variety of curricular and co-curricular programs taught by world-class American educators.” The K-12 program will also specialize in high-tech integration into the educational process from the earliest grade levels.
http://www.oasisis.org/news/2015/oasis-int...bandar-rimbayu/

So in comparison
1) Tenby will have more students e.g. 1800 vs 1200 for Oasis.
2) Tenby - UK based curriculum vs Oasis - American based curriculum