I am considering getting this bike:
https://bikesdirect.com/products/mercier/kilott_wt5.htm

I am trying to figure out what the gearing will be like so I visited Sheldon Browns site and used the gear calculator ( I read that a 18 tooth cog is also included with the bike so I am basing this with a 48t chainring, 18t cog and of course the SA s-rf5 IGH ) and came up with these numbers in gear inches:
115.2
96.0
72.0
54.0
45.0

I then assumed that I could simply use the calculator to calculate the gearing on my current bike wich happens to have the same size large chainring, 48t, so I punched in the numbers using 11-32 for my rear cogs thinking that I could then compare the two results and come up with the theoretical cog sizes of the internally geared hub.....But I am stupid and need help.
The numbers are in gear inches:
117.8
108.0
92.6
81.0
72.0
61.7
54.0
46.3
40.5

The best I can come up with is that the internal hub will have the "feel" of:

48/32 'ish

48/14 'ish

48/18

48/24

48/28 'ish

Does this seem about right?

if you used, say, the gear inch calculation , how you arrive at the number, say 61, doesn't matter whether its from
spinning a small wheel more often , or a 61" wheel once. as far as the pedal rotations for the distance traveled.

With the above correction I made it should be about right. I think you listed a typo. I would regear the bike as a 115" high gear is way too high for most riders under other than fast downhill riding conditions. A 21 tooth rear sprocket would give you a high of about 98" which is a more practical top gear for most people. Moving things down would also give a lower low gear of about 39".