I will respectfully disagree with two important aspects of this post. The 1800 does NOT "provides better mileage". I am sure that this poster means fuel miIeage. The 1800 provides substantially WORSE fuel mileage and a shorter range than the 1300.
The second point on which I disagree is the statement that the 1300 is an "older version as compared to 1800". They were produced at about the same time and, if you want to be exact, the 1800 is a bit older. According to Wikipedia (yes, I realize it is not always accurate but I looked at other sources as well which confirmed the Wikipedia info), the 1800 was first produced for the 2000 or 2001 model year (both years are cited in Wikipedia) while the 1300 was first produced for the 2002 or 2003 model year (again, both years are cited). Thus, the 1800 model is 1-2 years older than the 1300 model but the real key is that they are both about the same age - very early 2000s.
Lastly, I have no clue what this poster means by, "on the other hand, 1300 is also much better". Better than the 1800 I suppose but at what?