Is buying an iphone simply for Siri worth it?

I have an autoimmune disease and have issues with my memory and thinking at tines. Feels like my brain is foggy sometimes. I was wondering if Siri would benefit me? I was wondering if it is important to any users. The few people I know that have a iPhone 4s or 5 don't use it at all, however they are healthy and young. I just was wondering if it was worth the money. Its quite expensive, especially on a disability budget.

Will it depends on the person and what you do on the phone plus do you like apps?

It depends, the 4S has better hardware too. Hard to say though as everyone has different opinions on everything.

Unless you are also going to buy it for contacting people, I wouldn't buy it

You may be better off buying a iPod Touch 5th generation for $300. ( it has siri and does everything an iPhone does AND you don't have to pay monthly fees like the iPhone. )