I played Eye-2 clones (Pro Tour heads with Dynalite stiff shafts) from 1994 to 2009. Main reason I switched out was I needed to go to regular flex (I'm 60 now) and a more standard lie angle. About 2003 I went to a more upright stance, and the old irons were 2* flat to account for a "crouch" stance I had in 1994.
In the iron heads, I think we're seeing a cycle-back effect, where stuff comes back around about every five years. Key thing is to get the right head and the right shaft for your swing.
Using Golf Digest's three-kingdom classification, you have Players, GI and SGI clubs. Player's clubs have a high vertical center of gravity (VCOG), which allows you to keep the shots lower. SGI clubs have a low VCOG, which helps get the ball up.
Then you have all sorts of shafts.
During my switchover, I tried some BB and G10 irons SGI irons, both of which had high launch shafts. These two just got the ball up too high for me. I opted for the SGI Callaway X20s, which had a midlaunch Uniflex shaft and didn't balloon the ball.
This Christmas, I made a second change and got the X20 Tours, which have a smaller head and less offset than the X20 brother. I had tried the X20 Tours two years ago and really liked their feel, but was worried I might not be able to handle them. I took some lessons, stabilized my swing, and got the X20 Tours from Callaway Pre-Owned on holiday special for $342. With the trade-in on my X20s, I got never-been-hit clubs for a net $120.
Also, the X20 Tours - user-friendly GIs - are shafted in PX 5.0 Rifle Flighted... most off-the-rack versions carry 6.0 or DG S300, which are too stiff for me to flex.
Early tests of the irons between snow storms: I'm hitting solid shots center face, or hitting it out on the toe. Still have some residual "over the top" to tease out of my swing. But, you can tell on impact if you have a great, OK, or lousy shot.
Some people on the site like the heads, but reshaft to optimize their swing.