I purchased my first 4Runner in October 2015. I was also trying to decide between the Limited and SR5P. I live in Michigan and plenty of snow and ice here, so I was leaning towards the Limited only because of the AWD. However, I had an Xterra, so I knew the SR5 4x4 system would be fine.
I test drove both back-to-back and was concerned about the 20" tires on the Limited, but the dealer was willing to change with the SR5 I was also testing. As I was getting out of the Limited, the automatic floorboards came out (similar to when I opened the door to get in). That was the point that I decided there was no way I could own that Limited.
I bought a Super White 16 SR5P and it is amazing in the snow. I immediately switched the tires to Michelin LTX MS2. I got caught in a big storm in Wisconsin a while back - it's a tank. Yes, you have to be mindful of being on the dry pavement, but it's not a huge thing, at least I don't think so. In the end, it was less about the cost of the Limited and more about all the fancy stuff that came with it. I liked the AWD - didn't like the 20" tires, vented seats were okay (I liked the leather), wood trim was old and odd looking, I don't like auto climate control all that much, but when those floor boards came out, that was it - no sale. If it didn't have that option, I still think I would have ended up with the SR5P all things considered, but the boards made it feel very very fancy to me. I'm not knocking anyone who likes the fancy stuff - it's cool no doubt - just not my kind of SUV is all.
Power running boards are optional on the Limited. I didn't want them because my vehicle isn't lifted, currently, and I have no trust in them working consistently in the winter in Minnesota. I can't even keep ice out of the wheel wells....