For a lot of people there is a dip partway through the 2nd season, but I'd suggest you ride it out all the way to the end ….
I completely disagree. IMO, if the viewer quits mid-second season at the end of the Laura Palmer storyline, the show holds together as the greatest miniseries in TV history. If the viewer keeps going into the Windom Earle plot it's a huge letdown.
Not just because the show ends
but because, while the Palmer storyline more or less held together with the show playing fair with clues from day one
the subsequent storyline came off as being made up as it went along.