Gettings Prents to UK Either Long term Visit Visa or Family Visa

My parents live in India and are indian citizens. I am based in UK with family and settled as British citizens thru the Tier 2 category.
I am looking to get my parents to visit me more often without worrying about applying for VIsa.

Two methods I have seen:

1) Long term 2/5/10y Visit visa

2) Family Visa

Which would be a better and quicker way to get and is there any catch with any of the above methods. My parents wouldnt want to stay more than 6 months at a time, but having a long visa means they just have to get on a flight to UK to see us.

Please do suggest the procedure. My parents dont have any one else to take care of them in India, thus being with us will help them.

Have they had a UK visitor visa previously?

Also see my response to a very similar question earlier.