I think the success of the TeleVue 102 and the Takahashi FS 102 refractors is because they are doublet APOs designed for the visual observer. I've seen people on AstroMart sell the more expensive TeleVue NP-101 in favor of the TeleVue 102 doublet refractor. When it comes to buying refractors, people have highly personal criteria for buying them. I've never looked through an achromatic telescope but I plan on viewing through one sometime this summer. Some people prefer a longer focal length refractor for viewing planets and doubles. I've looked into the D&G line of achromat refractors and I've been to the D&G website and viewed the customer comments on their fine quality refractors. I like to read Sissy Haas reports with her 5" D&G in Sky and Telescope magazine. If I had an observatory, I'd like to own an 8" D&G someday. I think they are a good value for the money but they require a beefy mount. Any refractor over 6 inches gets a bit bulky for me to lug around. Debie