The CFI in Seletar has a very good reputation in the region.He has trained several PPL's who has gone on to drive for SQ,CX and 1st Singaporean female pilot in Mi.
I think training in a crowded area [Seletar] is great for increasing SA, and also the intense radio environment will give you a good grounding.And who says you have to stick in the area, Nav Ex takes you up to WMKM.
With regards to WMKJ, Asked around and try to find out what happened to 4 beautiful Cessna's in 3 years. I.e they converted all the C 172 to retractables!