Audio Craft AC-4400 and related AC tonearms

The AC3300 & AC4400 were in production for quite a long time. Here's a review of Platine Verdier from 2001 and it came with an AC4400, which looks to have been one of the recommend tonearms to go with the Verdier:
http://hifishack.com/jcv_platine_review.php

I'm very interested in the FR66s & FR66fx, but they are out of my budget... The difference, I believe, is the same as between FR64s & FR64fx: the former is stainless steel and the latter is aluminium. The anti-skating mechanisms are also different.

64fx or 66fx have lower effective mass than 64s or 66s, respectively. I think they are indeed made of aluminum . Otherwise, they appear to be identical to the s versions.

@lewm there is one thing i don't understand about those FX tonearms. They are black, the FR-7f is also black, they looks like they are made for each other, but the FX is lower mass tonearm. 

@chakster I think you read too much into the color match. The headshells that came with FR66s & FR64s were also black. 

What is compliance of 7f cartridge? The fx tonearms are indeed lower in mass than are the s tonearms but that's like saying your friend has lost 100 lbs and now weighs "only" 300 lbs. ( the s tonearms especially the 66s are very high in effective mass). Thus the 7f may well be suited to the fx tonearms even if its compliance is on the low side.