I have a question on Aviva requiring the company appointed medical doctor to verify the disability portion. Does this severely disadvantage the insured as in Aviva might play a part in influencing the doctor judgement?
If it's Aviva appointing the doctor, I'd probably be concerned about that. If it's the employer appointing the medical doctor, that might be OK.
I'd have to see the exact language in the policy documents, really. Maybe Aviva is less ambiguous about who judges disability, and that might be a good thing. Or maybe Aviva is more narrow, which might not be a good thing.
By the way, DIYinsurance (I have no affiliation) rebates 50% of the sales commission on Aviva Ideal Income, so that'd be a nice bonus if you decide that policy is the right fit. The current 35% premium discount promotion (for signups through June 30, 2018) is also passed on.
I don't think DII premiums are guaranteed level, by the way.
Aviva has a lower S&P rating than either AIA or Great Eastern. Below PPF Scheme limits, that probably doesn't matter. However, I think disability income insurance is highly likely to be above PPF Scheme limits, so the insurer's creditworthiness matters.
It is possible to buy DII from two or more insurers, although that's a little more complicated of course, and you have to be careful of aggregate limits if I'm not mistaken. For example, let's suppose you're earning $7,000/month currently. Both Aviva and AIA let you insure up to 75% of that income, or up to $5,250/month. So hypothetically you could buy $3,000/month from Aviva (to get the 35% premium discount) and $2,000/month from AIA. That's $5,000/month of total coverage, and that's below the 75% limit that both insurers have. I don't think there's any problem with that arrangement, as long as you don't lie to either insurer if they ask. The complication is that you have two claims to file if you're disabled, and conceivably both insurance companies could require their own medical exams if they wish. But maybe splitting your loyalties makes sense, just to defend yourself better against unlikely but possible insurer bankruptcy and/or future premium adjustments you don't like.
I also cannot seek treatment in my preferred hospital?
You can treat yourself in whatever hospital you want, with whatever you can afford. Disability income insurance doesn't concern itself with that detail, but DII obviously needs to determine whether you're disabled (as the policy defines it) or not -- there's some process defined in the policy to determine that. Usually these policies require you to submit to some reasonable medical examination(s) before the insurer will pay benefits, or for the insurer to maintain benefit payments. And you don't always or even very often get to pick that particular medical examiner, but I would be concerned if the examiner is set up in such a way as to be possibly less than neutral and impartial.