No medical check up is needed. What you need to do is to answer the health question only. Simple, but tons of question waiting there for you to answer. There is an online chat at the right bottom of their site that you can seek for help or you can email to them. 
Medical and life insurance are necessary in every age. It's depend on what you want actually. For me, I seek for cheap premium and I go for term life, but still needs other sifu to explain the actual concept. Interest to find out whether term insurance is better or life insurance is better.

Yea, because life insurance include with cash value and others while term are not return to you anything. Which is a pure life insurance.

It is never a mistake, in fact you can talk to your agent and see how and where you can reduce the premium commitment.

Ask your agent to
1. lay out what exactly is covered.
2. explain thoroughly
3. And the tell him/her your situation on affordability.

I do regular reviews with my customers too.

I am not that expert to judge, but monthly premium rm300 could be a burden. Good things, as the others stated you still can talk to your agent and request to reduce the premium commitment, but have to depend on your policy. By the way, my term premium currently cost me rm53 per month only.