Does anyone have experience using the original iPad mini, as well as the retina version? I have the original iPad mini, and I find it to be extremely useful. It has replaced about 85-90% of my needs for a Mac, and I carry it everywhere, since it's so portable. I much prefer it over using the iPhone for emails, web surfing and document viewing.
The times that I've looked at the retina iPad minis in the store, I don't see any difference in the displays for regular use. I rarely have to zoom in on mine, and my old eyes are far from being perfect. The only time I've been able to see a difference in the retina screen is if you zoom in to the point that you're fitting one or two letters per screen, which no one does in regular use.
I have used both along with an iPad 2 and iPad 3. I moved from the iPad 3 to the original iPad Mini just to give the form factor a try and loved it. Hated the drop in screen quality but loved the size. The processor and RAM could have been better as well in the mini but when I bought it I knew it was just a hold me over type thing until the rMini came out later that year. I ended up giving the Mini to my 5 year old in a Griffin Survivor case. She uses it to watch Netflix, iTunes movies I download for her, TV shows, kids games, etc... It is great for in the car and we are traveling.
The rMini though is awesome IMO. It is my daily driver for most of my computing needs. I love that it is small and able to fit in my cargo pants/shorts pockets. It can fit inside some of my jacket pockets or even just carrying it in my hands. It is small, light, very easy to hold for extended periods of time. I read kindle books on it, watch TV shows/movies on it streamed from my Mac Mini upstairs, Netflix, Crackle, Hulu+, use Safari for web browsing, stock mail app for email, imessage, skype, etc... I switch to a windows laptop or my Mac Mini if I need to do more than what the ipad can do but for daily requirements the ipad rmini does most of what I need. The battery last about 10 hrs which is a big selling point. I have a 16GB cellular model so I love being able to take it out while I am away from the house and use it without having to tether it first to my iPhone 5 (something I have to do with my Dell Venue 8 Pro tablet).
I am currently testing other options out. I currently am using an Asus Transformer T100 (64GB model) and a Dell Venue 8 Pro (64GB model). I didn't want a windows pro tablet for a while due to the batteries sucked. Now they are not so bad. Standby battery life still not that great unless you shut them completely down but they will last about 8-10 hrs now. The Asus is a bit big for me. Works great but large. That is why I gave the iPad 3 to my wife and I went with the mini for me. The Dell Venue is smaller, about as wide as the rmini but about half an inch longer than the rmini. Screen quality definitely goes to the rmini though. It is nice to have a full operating system at your fingertips though. I love how the ipad integrates with my Mac Mini and ATV3 setup at home. Airplay, Remote App, access my videos and music easily. Granted with file sharing turned on I can access my movies, TV shows, and music on my Dell Venue as well. The App selection on the Dell suck though. Luckily it is a full operating system so I am not tied to just those apps.
In the end I would go for the rmini but you will have to ask yourself do you want a larger more vibrant screen (iPad Air) or do you want the smaller form factor of the rmini.
As for upgrading from the mini to rmini.........yes. It is leaps and bounds better than the first mini. See if you can get a refurbished one so it will bring the price down a bit.