I'm not an exclusive refractor guy, but I have had several that stood out:
Tasco 6TE: I started out with this one. It introduced me to solar projection, Saturn's rings, Jupiter's larger belts, and some larger clusters.
Cheapo Japanese 60mm, 700mm fl: Mainly my first spotting scope, using a hybrid diagonal at the focus tube, and a second diagonal at right angles. With a Jaegers 32mm surplus eyepiece I identified my first flamingo at a German, North Sea wildlife refuge.
Pentax 80mm, 900mm fl: The scope that showed just how lousy my Astroscan and C8 were. It also gave me a lifetime memory of Eta Carinae from the summit of Haleakala.
C102, 1000mm fl: No-one less than Walter Scott Houston looked at it at Stellafane and pronounced it sub-optimal, because it failed even to make the Sidgewick standard. It had other issues. This was a Halley scope, and it came with a depression in the center of the rear element. It ran out of gas at 200x. Eventually, I sent it to D&G Optical for refiguring. I got it back, and found it sharp at 240x. Noticeable chromatic aberration. Sold it.
C80ED: This one most people know about, and the optics run out of gas above 225x. Why above? Because 225 is as high as a Baader zoom and a 3x Barlow will go.
SW120 Pro-ED: Venus at 150x was color free. The moon at 360x has some chromatic aberration. This scope has done very well on a variety of objects, including Mars, where I saw the "canals" for the first time, and clouds over where Olympus Mons should be.
I have looked through a lot of other refractors, including 6" Astro Physics (EDT) and Lunt scopes, and a 130mm EDF. The comparison with the 130mm was instructive. It taught me that my 120mm isn't going anywhere.