I have a second generation apple TV. At the time I got it the HD standard for apple tv was 720p. Many display devices were not better than that, so it was okay . Today most monitors, projectors and TV’s do a minimum of 1080p.
Apple TV Options
I was surprised to find a new generation 3 apple TV was the same price as my gen 2, about $90 cdn (could vary slightly if retailer has a sale on).
The main difference between the gen 2 and gen 3 is the availability of 1080p resolution. Gen 3 has an A5 processors vs. the A4 in the gen 2 device but the A5 dual core is not active and the clock speed the same on both by default (1 gigahertz)
Finally there is the gen 4 which comes with 32 gig storage ($190) or 64 gig ($260). interesting that they brought device storage back (gen2 and 3 basically have none, although gen 1 had 40 or 80 gig)
The gen 4 processor has an A8 processorwith the dual core activated and 1.4 gigahertz. It also has a rechargable Siri remote (worth $89 if purchased on it’s own) vs. the manual replacable battery remote on gen 2 and 3 (no Siri, no bluetooth)
Available New
Both gen 3 and 4 are available new. Given the heavy competion in set top TV boxes (Roku, Android like Kodi, Gobbang, etc) Apple wants to make sure they a competively priced device that features the iStore.
They still want to offer a technology upgrade for those that want it, albeit at a higher price point. This case the target is not new set top TV buyers ( whom will buy from the iStore) but more upgraders.
Given iStore sales are a real profit driver more so than the hardware, Apple continues to sell and market both gen 3 (focused on new buyers) and gen 4 (focused on functionality upgraders.
Pretty smart on Apples part. I went for the gen 4 because the remote connects via blue tooth so does not need IR line of site – that was a big pain for me.