They are awesome boats. I had one for about 6 years, sailed her to Bermuda
and back, among a lot of other sailing. Incredibly comfortable, very good performance. Possibly the easiest and most forgiving boat I've ever sailed (simply impossible to make her pound, and she carries her sail very well, even at higher winds). Likewise, the build quality is very very good. Built at the same factory and by the exact same people as the Aldens. I've not heard of any problems with the rig, as someone else suggested. The early hull
numbers (I had number 2) were more undercanvassed than the later ones, as the company was more conservative with the freestanding rig at that point. Many owners increased the sail area by raising the hoist for the jib
and/or adding a stainless steel
sprit to get a larger fore-triangle.
I really can't speak highly enough of the boat, and often question whether we made the right call moving to a different one (we just needed/wanted something with three cabins).
Good luck with your search, but you certainly would not be unhappy with an F45.