'99-'00 172R vs 172SP: R is good? or the weak little brother?

Just doing some looking at the difference, or perceived differences between the earlier (1998, 1999, 2000) 172Rs and the 172SPs. And besides the extra kW rating of the same size engine to produce the 180hp (on the SP) over the 160hp (on the R), I can't find much else different. (with the exception of maybe the leather seats, also on the SP.)
If anyone has flown both of these, is the difference (in hp) so much that the R is just too underpowered, or does the SP run at a higher RPM to achieve the extra hp, so that may be a negative? (I think I read that the R has 2,200 TBO and the SP 2,000 TBO, just to throw it out there).
Or, is it just that the R is a very nice plane and the SP, is the same thing, with just a little more pep if you need/want it.
Or put another way, are you just as excited to rent/fly an SP as an R?

Any thoughts or input, I'd be interested to hear.