or do I need to buy an entirely separate case? I have heard that if you go from 6 to 6s with a 6 case, the phone doesn't operate properly or it's too tight etc. Or, should I get a 6s case for the 6?

see review: http://www.amazon.com/review/R1EGQFD03FREB9/ref=ask_dp_lswr_rp_hza

getting a 6 thursday, and then in december I am gifting that phone to my girlfriend so I can get the 6s with another upgrade on my account. She doesn't have a contract with at&t so her phone costs are like $750+ (workin on it lol)

So recently I installed the Otterbox Defender Case on my iPhone 6. I planned on buying this only because I was impressed on how much it protects the phone from every angle. Even though I rarely would "accidentally" drop an expensive phone, I decided not to risk any chances and ended up buying the case.

On first moment, it looked great. Yeah a little thick, but it still protected all angles of the phone.

Here are three complaints, the last one being stressed:

... One thing I noticed right away is the screen protector. It is so hard to touch and tap the phone. Sometimes, you have to press the screen 3 times hard for the touch to input. By the way, it is virtually impossible to get Control Center open on the phone. The screen protector flap is blocking the screens pathway for the user to swipe for control center. It takes about 3 well effort tries to get control center open.

Another is the physical buttons. They are so hard to press! You can't simply just take your index finger and press the power button. No - you have to either put lots of effort on your thumb or use the side of your thumb finger and press it. I mean, I'm not sure how many times I would accidentally press the button so I hate how the buttons are so hard. On other otterbox cases, they aren't.

Finally, the one I'm most concerned about. The Touch ID home button. After a day of use, to my shock, I found that the Touch ID home button had a stain on it and felt sticky! And I ensure that I never had any foods or drink and spilled it. No, it appears that the screen protector is causing this. I even looked this problem up on google and saw that I'm not the only one facing this issue. Because of this, Touch ID works 40-50% of the time, is slow loading, and is also sticky and unresponsive.

I plan on switching to either the Otterbox Commuter or Otterbox Symmetery - a little more towards Symetery. I am still conducting more research.

Thanks.