Alan is well known for these "screwed and glued" aluminum frames. As as quality goes... your mileage will vary. The early models were not so reliable. The Alan cyclocross is world famous and pretty desireable... very nice looking bike. Just me personally but I would shy away from used aluminum. I am biased though, all my rides are steel. Torelli and Guerciotti both sold Alan frames under their marquee... so they do not have a rep as being junk, as far as aluminum goes