I think te Henry is nice looking, like the sights and like that I can use my M&P mags in it. Also like the tang safety. In fact I like everything abou tit except for the price.
Ruger-kinda quirky looking compared to the Henry,BUT is takedown and has the Ruger name behind it. BUT it requires me to buy a whole new set of Magazines (Glock or Ruger). It is also around $200 cheaper than the Henry.
Discussion is open for comments either way.
I have several 9mm carbines and like them. Fun to shoot, and offer increased muzzle velocity over a handgun. I chronographed several guns just yesterday found some interesting results. The ammo used was some Winchester 115gr JHP:
Diamondback DB9 Gen 4, 2-7/8" - 1061 fps
Sig P365, 3-1/2" - 1105 fps
Glock 19 Gen 1, 4" - 1170 fps
KelTec Sub 2000, 16" - 1337 fps
Pretty obvious that the 16" barrel of the KelTec adds a couple of hundred fps or so. The Ruger and Henry also have 16" barrels and so should provide a comparable performance boost. There is also an increase in practical accuracy.
I like the KelTec for its compact size and lightness, and the folding feature is kinda neato. The "iron" sights on it are virtually unusable, an optic of some kind is nearly mandated. I put a red dot sight on it using a 45 degree side mount so that it will still fold. An alternative would be a quick-detach sight mount, or just leave it unfolded - it's still very compact either way.
I also have the Ruger PCC which by comparison to the KelTec feels heavy and solid, which has its own appeal. Both are set up for Glock mags, but the KelTec can also be had in S&W M&P or Sig flavor, and even in .40 S&W.
By the way, KelTec has a $100 rebate for purchases of a new Sub2000 through June 30, 2023. That's what tipped me over the edge to buy one, after rebate my total price was $376 (not including the RDS).